Movable body apparatus, moving method, exposure apparatus, exposure method, flat-panel display manufacturing method , and device manufacturing method

ABSTRACT

A movable body apparatus has: a substrate holder holding a substrate and can move in the X and Y-axes directions; a Y coarse movement stage movable in the Y-axis direction; a first measurement system acquiring position information on the substrate holder by heads on the substrate holder and a scale on the Y coarse movement stage; a second measurement system acquiring position information on the Y coarse movement stage by heads on the Y coarse movement stage and a scale; and a control system controlling the position of the substrate holder based on position information acquired by the first and second measurement systems. The first measurement system irradiates a measurement beam while moving the heads in the X-axis direction with respect to the scale, and the second measurement system irradiates a measurement beam while moving the heads in the Y-axis direction with respect to the scale.

TECHNICAL FIELD

The present invention relates to a movable body apparatus, a movingmethod, an exposure apparatus, an exposure method, a flat-panel displaymanufacturing method, and a device manufacturing method.

BACKGROUND ART

In a lithography process to manufacture electronic devices(micro-devices) such as a liquid crystal display device or asemiconductor device (such as an integrated circuit), an exposureapparatus is used, which, by exposing a photosensitive glass plate or awafer (hereinafter collectively called a “substrate”) to an illuminationlight (an energy beam) via a projection optical system (a lens),transfers a predetermined pattern that a mask (photo mask) or a reticle(hereinafter collectively called a “mask”) has onto the substrate.

As an exposure apparatus of this kind, since position control of thesubstrate with respect to the projection optical system has to beperformed with high precision, an apparatus is known that uses anencoder system as a position measurement system of the substrate (forexample, refer to PTL 1).

Here, in the case of obtaining position information on the substrateusing an optical interferometer system, since the optical path of thelaser to the bar mirror becomes long, influence of air fluctuationcannot be ignored.

CITATION LIST Patent Literature

[PTL 1] U.S. Patent Application Publication No. 2010/0266961

SUMMARY OF THE INVENTION Means for Solving the Problems

According to a first aspect of the present invention, there is provideda movable body apparatus, comprising: a first movable body holding anobject that can move in a first direction and a second directionintersecting with each other; a first measurement system that measuresposition information on the first movable body in the first direction,the system in which one of a first grating area with a plurality ofgrating areas arranged mutually apart in the first direction thatincludes measurement components in the first direction and the seconddirection and a plurality of first heads irradiating the first gratingarea with a measurement beam while moving in the first direction isprovided at the first movable body, and of the plurality of the firstheads, position information on the first movable body in the firstdirection is measured by at least three first heads irradiating themeasurement beam on at least one of the plurality of grating areas; asecond movable body that can move in the second direction, beingprovided at the other of the first grating area and the plurality offirst heads; a second measurement system that measures positioninformation on the second movable body in the second direction, thesystem in which one of a second grating area including measurementcomponents in the first direction and second direction and a second headirradiating the second grating area with a measurement beam while movingin the second direction is provided at the second movable body, and theother of a second grating area and the second grating area is providedfacing the second movable body; and a control system that controlsmovement of the first movable body in directions of three degrees offreedom within a predetermined plane including the first direction andthe second direction, based on the position information measured by thefirst measurement system and the second measurement system, andcorrection information to compensate for measurement error of themeasurement system occurring due to at least one of the first gratingmember, the plurality of first heads, and movement of the movable body.

According to a second aspect of the present invention, there is provideda movable body apparatus that exposes a substrate with an illuminationlight via an optical system, comprising: a movable body arranged belowthe optical system that holds the substrate; a drive system that canmove the movable body in a first direction and a second directionorthogonal to each other within a predetermined plane orthogonal to anoptical axis of the optical system; a measurement system in which one ofa grating member with a plurality of grating areas arranged mutuallyapart in the first direction and a plurality of first heads eachirradiating the grating member with a measurement beam that can move inthe second direction is provided at the movable body, and the other ofthe grating member and the plurality of first heads is provided facingthe movable body, the measurement system having a measurement device inwhich one of a scale member and a second head is provided at theplurality of first heads and the other of the scale member and thesecond head is provided facing the plurality of the first heads, and themeasurement device measuring position information on the plurality offirst heads in the second direction by irradiating the scale member witha measurement beam via the second head, the measurement system measuringposition information on the movable body in at least directions of threedegrees of freedom within the predetermined plane, based on measurementinformation on at least three first heads of the plurality of firstheads irradiating at least one of the plurality of grating areas withthe measurement beam and measurement information on the measurementdevice; and a control system, controlling the drive system based oncorrection information to compensate for measurement error of themeasurement device caused by one of the scale member and the secondhead, and position information measured by the measurement system,wherein with each of the plurality of first heads, the measurement beammoves off from one of the plurality of grating areas, and moves toirradiate another grating area adjacent to the one of the plurality ofgrating areas, while the movable body is moving in the first direction.

According to a third aspect of the present invention, there is providedan exposure apparatus, comprising: the movable body apparatus accordingto the first or second aspect, and an optical system that irradiates theobject with an energy beam, and exposes the object.

According to a fourth aspect of the present invention, there is provideda flat-panel display manufacturing method, comprising: exposing asubstrate using the exposure apparatus according to the third aspect;and developing the substrate that has been exposed.

According to a fifth aspect of the present invention, there is provideda device manufacturing method, comprising:

exposing a substrate using the exposure apparatus according to the thirdaspect; and developing the substrate that has been exposed.

According to a sixth aspect of the present invention, there is provideda moving method, comprising: moving a first movable body holding anobject in a first direction and a second direction intersecting eachother; measuring position information on the first movable body in thefirst direction by a first measurement system, in which one of a firstgrating area with a plurality of grating areas arranged mutually apartin the first direction that includes measurement components in the firstdirection and the second direction and a plurality of first headsirradiating the first grating area with a measurement beam while movingin the first direction is provided at the first movable body, and of theplurality of the first heads, position information on the first movablebody in the first direction is measured by at least three first headsirradiating the measurement beam on at least one of the plurality ofgrating areas; moving the first movable body in the second direction bya second movable body provided at the other of the first grating areaand the plurality of first heads; measuring position information on thesecond movable body in the second direction by a second measurementsystem, in which one of a second grating area including measurementcomponents in the first direction and second direction and a second headirradiating the second grating area with a measurement beam while movingin the second direction is provided at the second movable body, and theother of a second grating area and the second grating area is providedfacing the second movable body; and controlling movement of the firstmovable body in directions of three degrees of freedom within apredetermined plane including the first direction and the seconddirection, based on the position information measured by the firstmeasurement system and the second measurement system, and correctioninformation to compensate for measurement error of the measurementsystem occurring due to at least one of the first grating member, theplurality of first heads, and movement of the first movable body.

According to a seventh aspect of the present invention, there isprovided an exposure method, comprising: moving the object in the firstdirection by the moving method according to the sixth aspect; andirradiating the object moved in the first direction with an energy beam,and exposing the object.

According to an eighth aspect of the present invention, there isprovided a flat-panel display manufacturing method, comprising: exposinga substrate using the exposure method according to the seventh aspect;and developing the substrate that has been exposed.

According to a ninth aspect of the present invention, there is provideda device manufacturing method, comprising: exposing a substrate usingthe exposure method according to the seventh aspect; and developing thesubstrate that has been exposed.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a view schematically showing a structure of a liquid crystalexposure apparatus according to a first embodiment.

FIG. 2 is a view showing a substrate stage device that the liquidcrystal exposure apparatus in FIG. 1 has.

FIG. 3 is a schematic view of a substrate measurement system that theliquid crystal exposure apparatus in FIG. 1 has.

FIG. 4 is a view (No. 1) used to explain an operation of a substratestage device.

FIG. 5 is a view (No. 2) used to explain an operation of a substratestage device.

FIG. 6 is a block diagram showing an input/output relation of a maincontroller that mainly structures a control system of the liquid crystalexposure apparatus.

FIG. 7 is a planar view showing a substrate stage device according to asecond embodiment.

FIG. 8 is a cross-section view of the substrate stage device in FIG. 7.

FIG. 9 is a view showing a second system of the substrate stage devicein FIG. 7.

FIG. 10 is a view showing a first system of the substrate stage devicein FIG. 7.

FIG. 11 is a planar view showing a substrate stage device according to athird embodiment.

FIG. 12 is a cross-section view of the substrate stage device in FIG.11.

FIG. 13 is a view showing a second system of the substrate stage devicein FIG. 11.

FIG. 14 is a view showing a first system of the substrate stage devicein FIG. 11.

FIG. 15 is a planar view showing a substrate stage device according to afourth embodiment.

FIG. 16 is a cross-section view of the substrate stage device in FIG.15.

FIG. 17 is a view showing a second system of the substrate stage devicein FIG. 15.

FIG. 18 is a view showing a first system of the substrate stage devicein FIG. 15.

FIG. 19 is a planar view showing a substrate stage device according to afifth embodiment.

FIG. 20 is a cross-section view of the substrate stage device in FIG.19.

FIG. 21 is a view showing a second system of the substrate stage devicein FIG. 19.

FIG. 22 is a view showing a first system of the substrate stage devicein FIG. 19.

FIG. 23 is a view showing a substrate stage device according to a sixthembodiment.

FIG. 24 is a view showing a substrate holder which is a part of thesubstrate stage device in FIG. 23.

FIG. 25 is a view showing a system including a substrate table which isa part of the substrate stage device in FIG. 23.

FIG. 26 is a view used to explain a structure of a substrate measurementsystem according to the sixth embodiment.

FIG. 27 is a view used to explain an operation of a substratemeasurement system in FIG. 26.

FIG. 28 is a view showing a substrate stage device according to aseventh embodiment.

FIG. 29 is a view showing a substrate holder which is a part of thesubstrate stage device in FIG. 28.

FIG. 30 is a view showing a system including a substrate table which isa part of the substrate stage device in FIG. 28.

FIG. 31 is a view used to explain a structure of a substrate measurementsystem according to the seventh embodiment.

FIG. 32 is a view showing a substrate stage device according to aneighth embodiment.

FIG. 33 is a view showing a substrate holder which is a part of thesubstrate stage device in FIG. 32.

FIG. 34 is a view showing a system including a substrate table which isa part of the substrate stage device in FIG. 32.

FIG. 35 is a view used to explain a structure of a substrate measurementsystem according to the eighth embodiment.

FIG. 36 is a view showing a substrate holder which is a part of thesubstrate stage device in a ninth embodiment.

FIG. 37 is a view showing a system including a substrate table which isa part of a substrate stage device in the ninth embodiment.

FIG. 38 is a view used to explain a structure of a substrate measurementsystem according to the ninth embodiment.

FIG. 39 is a view showing a substrate holder which is a part of asubstrate stage device according to a tenth embodiment.

FIG. 40 is a view showing a system including a substrate table which isa part of a substrate stage device according to the tenth embodiment.

FIG. 41 is a view used to explain a structure of a substrate measurementsystem according to the tenth embodiment.

FIG. 42 is a cross-section view (No. 1) of the substrate stage deviceaccording to the tenth embodiment.

FIG. 43 is a cross-section view (No. 2) of the substrate stage deviceaccording to the tenth embodiment.

FIG. 44 is a view showing a substrate stage device according to aneleventh embodiment.

FIG. 45 is a view showing a substrate holder which is a part of thesubstrate stage device in FIG. 44.

FIG. 46 is a view showing a system including a substrate table which isa part of the substrate stage device in FIG. 44.

FIG. 47 is a view used to explain a structure of a substrate measurementsystem according to the eleventh embodiment.

FIG. 48 is a view showing a substrate stage device according to atwelfth embodiment.

FIG. 49 is a view showing a substrate holder which is a part of thesubstrate stage device in FIG. 48.

FIG. 50 is a view showing a system including a weight canceling devicewhich is apart of the substrate stage device in FIG. 48.

FIG. 51 is a view showing a system including a Y coarse movement stagewhich is a part of the substrate stage device in FIG. 48.

FIG. 52 is a view showing a system including a substrate table which isa part of the substrate stage device in FIG. 48.

FIG. 53 is a view used to explain a structure of a substrate measurementsystem according to the twelfth embodiment.

FIG. 54 is a view used to explain an operation of the substratemeasurement system in FIG. 53.

FIG. 55 is a view showing a substrate stage device according to athirteenth embodiment.

FIG. 56 is a view showing a substrate holder which is a part of thesubstrate stage device in FIG. 55.

FIG. 57 is a view showing a system including a substrate table which isa part of the substrate stage device in FIG. 55.

FIG. 58 is a view used to explain a structure of a substrate measurementsystem according to the thirteenth embodiment.

FIG. 59 is a view showing a substrate stage device according to afourteenth embodiment.

FIG. 60 is a view showing a substrate stage device according to afifteenth embodiment.

FIG. 61 is a view used to explain an operation of the substrate stagedevice in FIG. 60.

FIG. 62 is a view showing a substrate holder which is a part of thesubstrate stage device in FIG. 60.

FIG. 63 is a view showing a system including a substrate table which isa part of the substrate stage device in FIG. 60.

FIG. 64 is a view showing a substrate stage device according to asixteenth embodiment.

FIG. 65 is a view showing a substrate stage device according to aseventeenth embodiment.

FIG. 66 is a view showing a substrate stage device according to aneighteenth embodiment.

FIG. 67 is a view used to explain a structure of a substrate measurementsystem according to the eighteenth embodiment.

FIG. 68 shows a schematic view of a substrate measurement systemaccording to the eighteenth embodiment.

FIG. 69 is a view showing a substrate stage device according to anineteenth embodiment.

FIG. 70 shows a schematic view of a substrate measurement systemaccording to the nineteenth embodiment.

FIG. 71 is a planar view showing a substrate holder and a pair of headunits of a substrate measurement system that a liquid crystal exposureapparatus according to a twentieth embodiment has, along with aprojection optical system.

FIGS. 71A and 71B are views used to explain a movement range in anX-axis direction of a substrate holder when position measurement of thesubstrate holder is performed.

FIGS. 73A to 73D are views used to explain a first state to a fourthstate in a state change of positional relation between a pair of headbases and a scale in the process when a substrate holder moves in theX-axis direction in the twentieth embodiment.

FIGS. 74A to 74C are views used to explain a linkage process at the timeof switching heads of an encoder system that measures positioninformation on a substrate holder performed in the liquid crystalexposure apparatus according to the twentieth embodiment.

FIG. 75 is a planar view showing a substrate holder and a pair of headbases of a substrate encoder system that a liquid crystal exposureapparatus according to a twenty-first embodiment has, along with aprojection optical system.

FIG. 76 is a view used to explain a characteristic structure of a liquidcrystal exposure apparatus according to a twenty-second embodiment

FIG. 77 is a graph showing a measurement error of an encoder withrespect to a change in Z position at a pitching amount θy=α.

MODE FOR CARRYING OUT THE INVENTION First Embodiment

Hereinafter, a first embodiment will be described, using FIGS. 1 to 6.

FIG. 1 schematically shows a structure of an exposure apparatus (here,liquid crystal exposure apparatus 10) according to the first embodiment.Liquid crystal exposure apparatus 10 is a projection exposure apparatusof a step-and-scan method, or a so-called scanner, whose exposure targetis an object (here, a glass substrate P). Glass substrate P(hereinafter, simply referred to as “substrate P”) is formed in arectangular shape (square shape) in a planar view, and is used in liquidcrystal display devices (flat-panel displays) and the like.

Liquid crystal exposure apparatus 10 has an illumination system 12, amask stage device 14 that holds a mask M on which a circuit pattern andthe like is formed, a projection optical system 16, an apparatus mainsection 18, a substrate stage device 20 that holds substrate P whosesurface (a surface facing a +Z side in FIG. 1) is coated with a resist(sensitive agent), a control system for these parts and the like.Hereinafter, a direction in which mask M and substrate P are eachrelatively scanned with respect to projection optical system 16 at thetime of exposure will be described as an X-axis direction, a directionorthogonal to the X-axis direction in a horizontal plane will bedescribed as a Y-axis direction, a direction orthogonal to the X-axisand the Y-axis will be described as a Z-axis direction (a directionparallel to an optical axis direction of projection optical system 16),and rotation directions around the X-axis, the Y-axis, and the Z-axiswill each be described as a θx direction, a θy direction, and a θzdirection. Also, position in the X-axis, the Y-axis, and the Z-axisdirections will each be described as an X position, a Y position, and aZ position.

Illumination system 12 is structured similarly to the illuminationsystem disclosed in U.S. Pat. No. 5,729,331 and the like, and irradiatesmask M with a light emitted from a light source not shown (such as amercury lamp, or a laser diode) serving as an exposure illuminationlight (illumination light) IL, via a reflection mirror, a dichroicmirror, a shutter, a wavelength selection filter, various kinds oflenses and the like each of which are not shown. As illumination lightIL, light such as an i-line (wavelength 365 nm), a g-line (wavelength436 nm), or an h-line (wavelength 405 nm) (or, a synthetic light of thei-line, the g-line, and the h-line described above) is used.

As mask M that mask stage device 14 holds, a transmission type photomaskis used. On the lower surface (a surface facing the −Z side in FIG. 1)of mask M, a predetermined circuit pattern is formed. Mask M is moved inpredetermined long strokes in a scanning direction (the X-axisdirection) and also is finely moved appropriately in the Y-axisdirection and the θz direction by a main controller 100, via a maskdrive system 102 including a linear motor, an actuator such as a ballscrew device and the like (each of which are not shown in FIG. 1, referto FIG. 6). Position information (including rotation amount informationin the θz direction; the same applies hereinafter) of mask M within anXY plane is obtained by main controller 100 (each of which are not shownin FIG. 1, refer to FIG. 6), via a mask measurement system 104 includingan encoder system or a measurement system such as an interferometersystem.

Projection optical system 16 is arranged below mask stage device 14.Projection optical system 16 is a so-called multi-lens projectionoptical system having a structure similar to the projection opticalsystem disclosed in U.S. Pat. No. 6,552,775 and the like, and isequipped with a plurality of lens modules that form an upright normalimage with a double telecentric equal magnifying system.

In liquid crystal exposure apparatus 10, when illumination light ILilluminates an illumination area on mask M, illumination light IL havingpassed through (transmitted) mask M a projection image (partial uprightimage) of the circuit pattern of mask M within the illumination area isformed on an irradiation area (exposure area) of the illumination lighton substrate P conjugate with the illumination area, via projectionoptical system 16. Then by mask M relatively moving in the scanningdirection with respect to illumination area (illumination light IL)along with substrate P relatively moving in the scanning direction withrespect to the exposure area (illumination light IL), scanning exposureof one shot area on substrate P is performed, and the pattern formed onmask M is transferred on the shot area.

Apparatus main section 18 supports mask stage device 14 and projectionoptical system 16, and is installed on a floor F in a clean room via avibration isolation device 19. Apparatus main section 18 is structuredsimilarly to the apparatus main section disclosed in U.S. PatentApplication Publication No. 2008/0030702, and has an upper mount section18 a, a pair of middle mount section 18 b, and a lower mount section 18c. Since upper mount section 18 a is a member that supports projectionoptical system 16, hereinafter, in the embodiment, upper mount section18 a will be referred to and described as “optical surface plate 18 a.”Here, in the scanning exposure operation using liquid crystal exposureapparatus 10 in the embodiment, since position control of substrate P isperformed with respect to illumination light IL irradiated viaprojection optical system 16, optical surface plate 18 a that supportsprojection optical system 16 functions as a reference member whenperforming position control of substrate P.

Substrate stage device 20 is a device used to perform position controlof substrate P with high precision with respect to projection opticalsystem 16 (illumination light IL), that moves substrate P along ahorizontal plane (the X-axis direction and the Y-axis direction) inpredetermined long strokes and also finely moves substrate P indirections of six degrees of freedom. While the structure of thesubstrate stage device used in liquid crystal exposure apparatus 10 isnot limited in particular, in the first embodiment, as an example, asubstrate stage device 20 of a so-called coarse/fine movement structureis used that includes a gantry type two-dimensional coarse movementstage and a fine movement stage which is finely moved with respect tothe two-dimensional coarse movement stage, as is disclosed in U.S.Patent Application Publication No. 2012/0057140 and the like.

Substrate stage device 20 is equipped with; a fine movement stage 22, aY coarse movement stage 24, an X coarse movement stage 26, a supportsection (a weight canceling device 28 here) 22, a pair of base frames 30(one of the pair is not shown in FIG. 1, refer to FIG. 4), a substratedrive system 60 (not shown in FIG. 1, refer to FIG. 6) used to move eachcomponent structuring substrate stage device 20, a substrate measurementsystem 70 (not shown in FIG. 1, refer to FIG. 6) used to measureposition information on each component described above and the like.

As is shown in FIG. 2, fine movement stage 22 is equipped with asubstrate holder 32 and a stage main section 34. Substrate holder 32 isformed in a plate shape (or in a box shape) having a rectangular shapein a planar view (refer to FIG. 4), substrate P is mounted on its uppersurface (substrate mount surface). The size of the upper surface ofsubstrate holder 32 in the X-axis and Y-axis directions is set to aroundthe same size as (actually slightly shorter than) substrate P. SubstrateP, by being held by vacuum suction by substrate holder 32 in a statemounted on the upper surface of substrate holder 32, has its flatnesscorrected almost entirely (the entire surface) along the upper surfaceof substrate holder 32. Stage main section 34 consists of a plate shape(or a box shape) member having a rectangular shape in a planar viewwhose size in the X-axis and Y-axis directions is shorter than substrateholder 32, and is connected integrally to the lower surface of substrateholder 32.

Referring back to FIG. 1, Y coarse movement stage 24 is below (on the −Zside of) fine movement stage 22, and is arranged on the pair of baseframes 30. Y coarse movement stage 24, as is shown in FIG. 4, has a pairof X beams 36. The pair of X beams 36 is arranged parallel to the Y-axisdirection at a predetermined spacing. The pair of X beams 36 is mountedon the pair of base frames 30 via a mechanical linear guide device, andis freely movable in the Y-axis direction on the pair of base frames 30.

Referring back to FIG. 1, X coarse movement stage 26 is above (on the +Zside of) Y coarse movement stage 24, and is arranged below fine movementstage 22 (in between fine movement stage 22 and Y coarse movement stage24). X coarse movement stage 26 is a plate shape member having arectangular shape in a planar view, the stage being mounted on the pairof X beams 36 (refer to FIG. 4) that Y coarse movement stage 24 has viaa plurality of mechanical linear guide devices 38 (refer to FIG. 2), andthe stage is freely movable in the X-axis direction with respect to Ycoarse movement stage 24, while being moved integrally with Y coarsemovement stage 24 in the Y-axis direction.

As is shown in FIG. 6, substrate drive system 60 is equipped with; afirst drive system 62 for finely moving fine movement stage 22 indirections of six degrees of freedom (in each of the X-axis, the Y-axis,the Z-axis, the θx, the θy, and the θz directions) with respect tooptical surface plate 18 a, a second drive system 64 for moving Y coarsemovement stage 24 in long strokes in the Y-axis direction on base frames30 (each refer to FIG. 1), and a third drive system 66 for moving Xcoarse movement stage 26 in long strokes in the X-axis direction on Ycoarse movement stage 24 (each refer to FIG. 1). While the type ofactuators that structure the second drive system 64 and the third drivesystem 66 is not limited in particular, as an example, a linear motor, aball screw driver or the like can be used (FIG. 1 and the like show alinear motor).

While the type of actuators that structure the first drive system 62 isalso not limited in particular, in FIG. 2 and the like, as an example, aplurality of linear motors (voice coil motors) 40 is shown (X linearmotors are not shown in FIGS. 1 and 2) that generates thrust in each ofthe X-axis, the Y-axis, and the Z-axis directions. Each linear motor 40has a stator attached to X coarse movement stage 26, and also a moverattached to stage main section 34 of fine movement stage 22, and to finemovement stage 22, thrust is given in directions of six degrees offreedom via each linear motor 40 with respect to X coarse movement stage26. A detailed structure of each of the first to third drive systems 62,64, and 66, as an example, is disclosed in, U.S. Patent ApplicationPublication No. 2010/0018950 and the like; therefore, the descriptionthereabout will be omitted.

Main controller 100 gives thrust to fine movement stage 22 using thefirst drive system 62 so that relative position between fine movementstage 22 and X coarse movement stage 26 (each refer to FIG. 1) stayswithin a predetermined range in the X-axis and the Y-axis directions.Here, “position stays within a predetermined range,” on moving finemovement stage 22 with long strokes in the X-axis or the Y-axisdirection, is used merely to imply that X coarse movement stage 26 (inthe case fine movement stage 22 is moved in the Y-axis direction, Xcoarse movement stage 26 and Y coarse movement stage 24) and finemovement stage 22 are moved almost at the same speed in the samedirection, and that fine movement stage 22 and X coarse movement stage26 do not necessarily have to move in strict synchronization and apredetermined relative movement (relative position displacement) ispermissible.

Referring back to FIG. 2, weight canceling device 28 is equipped with aweight canceling device 42 that supports the weight of fine movementstage 22 from below, and a Y step guide 44 that supports weightcanceling device 42 from below.

Weight canceling device 42 (also referred to as a central pillar) isinserted into an opening section formed in X coarse movement stage 26,and is mechanically connected at the height of the center-of-gravityposition to X coarse movement stage 26, via a plurality of connectingmembers 46 (also referred to as a flexure device). X coarse movementstage 26 and weight canceling device 42 are connected by the pluralityof connecting members 46, in a state of vibratory (physical) separationin the Z-axis direction, the θx direction, and the θy direction weightcanceling device 42, by being pulled by X coarse movement stage 26,moves integrally with X coarse movement stage 26, in the X-axis and/orthe Y-axis direction.

Weight canceling device 42 supports the weight of fine movement stage 22from below in a non-contact manner via a pseudospherical bearing devicecalled a leveling device 48.

This allows relative movement of fine movement stage 22 in the X-axis,the Y-axis, and θz direction with respect to weight canceling device 42and oscillation (relative movement in the θx and θy directions) withrespect to the horizontal plane. As for the structure and function ofweight canceling device 42 and leveling device 48, an example isdisclosed in U.S. Patent Application Publication No. 2010/0018950 andthe like; therefore, the description thereabout will be omitted.

Y step guide 44 consists of a member extending parallel to the X-axis,and is arranged in between the pair of X beams 36 that Y coarse movementstage 24 has (refer to FIG. 4). The upper surface of Y step guide 44 isset parallel to the XY plane (horizontal plane), and weight cancelingdevice 42 is mounted on Y step guide 44 in a non-contact manner, via anair bearing 50. Y step guide 44 functions as a surface plate when weightcanceling device 42 (that is, fine movement stage 22 and substrate P)moves in the X-axis direction (scanning direction). Y step guide 44 ismounted on lower mount section 18 c via a mechanical linear guide device52, and while being freely movable in the Y-axis direction with respectto lower mount section 18 c, relative movement in the X-axis directionis restricted.

Y step guide 44 is mechanically connected (refer to FIG. 4) at theheight of the center-of-gravity position to Y coarse movement stage 24(the pair of X beams 36), via a plurality of connecting members 54.Connecting members 54 are flexure devices similarly to connectingmembers 46 described above that connect Y coarse movement stage 24 and Ystep guide 44 in a state of vibratory (physical) directions of fivedegrees of freedom; excluding the Y-axis direction in directions of sixdegrees of freedom. Y step guide 44, by being pulled by Y coarsemovement stage 24, moves integrally with Y coarse movement stage.

The pair of base frames 30, as is shown in FIG. 4, each consists of amember extending parallel to the Y-axis, and is installed parallel toeach other on floor F (refer to FIG. 1). Base frames 30 are physically(or vibrationally) separate from apparatus main section 18.

Next, substrate measurement system 70 for obtaining position informationon substrate P (actually, fine movement stage 22 holding substrate P) indirections of six degrees of freedom will be described.

FIG. 3 shows a schematic view of substrate measurement system 70.Substrate measurement system 70 is equipped with; a first measurementsystem (here, a fine movement stage measurement system 76 (refer to FIG.6)) including a first scale (here, an upward scale 72) that Y coarsemovement stage 24 has (associated with Y coarse movement stage 24) and afirst head (here, downward X heads 74 x and downward Y heads 74 y) thatfine movement stage 22 has, and a second measurement system (here, acoarse movement stage measurement system 82 (refer to FIG. 6)) includinga second scale (here, a downward scale 78) that optical surface plate 18a (refer to FIG. 2) has and a second head (here, upward X heads 80 x andupward Y heads 80 y) that Y coarse movement stage 24 has. Note that inFIG. 3, fine movement stage 22 is shown, modeled as a member holdingsubstrate P. Also, spacing (pitch) between gratings in a diffractiongrating that each of the scales 72 and 78 has is illustrated greatlywider than the actual spacing. The same applies to other drawings aswell. Also, since the distance between each head and each scale isgreatly shorter than the distance between a laser light source and a barmirror of a conventional optical interferometer system, influence of airfluctuation is less than that of the optical interferometer system,which allows position control of substrate P with high precision so thatthe exposure accuracy can be improved.

Upward scale 72 is fixed to the upper surface of a scale base 84. Scalebase 84 is arranged as is shown in FIG. 4, one on the +Y side and one onthe −Y side of fine movement stage 22. Scale base 84, as is shown inFIG. 2, is fixed to X beams 36 of Y coarse movement stage 24, via an armmember 86 formed in an L-shape when viewed from the X-axis direction.Accordingly, scale base 84 (and upward scale 72) can be moved inpredetermined long strokes in the Y-axis direction integrally with Ycoarse movement stage 24. As for arm member 86, as is shown in FIG. 4,while two are arranged separately in the X-axis direction for one X beam36, the number of arm member 86 is not limited to this, and can beappropriately increased or decreased.

Scale base 84 is a member extending parallel to the X-axis, and thelength in the X-axis direction is set to around twice the length (aboutthe same as Y step guide 44) in the X-axis direction of substrate holder32 (that is, substrate P (not shown in FIG. 4)). Scale base 84 ispreferably formed with a material such as ceramics and the like thathardly generates thermal deformation. The same applies to other membersto be described later on; scale base 92, and head bases 88 and 96.

Upward scale 72 is a plate shaped (strip shaped) member extending in theX-axis direction, and on its upper surface (a surface facing the +Z side(upper side)), a reflection type two-dimensional grating (so-calledgrating) is formed whose periodic direction is in two-axis directions(in the embodiment, X-axis and Y-axis directions) orthogonal to eachother.

To each of the center section of the side surface on the +Y side and −Yside of substrate holder 32, head base 88 is fixed (refer to FIG. 2) viaan arm member 90 corresponding to scale base 84 described above. Each ofthe downward heads 74 x and 74 y (refer to FIG. 3) is fixed to the lowersurface of head base 88.

In fine movement stage measurement system 76 (refer to FIG. 6) of theembodiment, as is shown in FIG. 3, to one head base 88, two downward Xheads 74 x are arranged separately in the X-axis direction, and twodownward Y heads 74 y are arranged separately in the X-axis direction.Each of the heads 74 x and 74 y irradiates the corresponding upwardscale 72 with a measurement beam, and also receives light (here, adiffracted light) from upward scale 72. Light from upward scale 72 issupplied to a detector not shown, and the output of the detector issupplied to main controller 100 (refer to FIG. 6). Main controller 100obtains relative movement amount of each of the heads 74 x and 74 y withrespect to scale 72, based on the output of the detector. Note that inthe description, “head” simply means a section that emits a measurementbeam onto a diffraction grating as well as a section where light fromthe diffraction grating is incident on, and the head itself illustratedin each of the drawings does not have to have a light source and adetector.

As is described so far, in fine movement stage measurement system 76 ofthe embodiment (refer to FIG. 6), with the total of four (two each onthe +Y side and the −Y side of substrate P) downward X heads 74 x andthe corresponding upward scale 72, four X linear encoder systems arestructured, and with the total of four (two each on the +Y side and the−Y side of substrate P) downward Y heads 74 y and the correspondingupward scale 72, four Y linear encoder systems are structured. Maincontroller 100 (refer to FIG. 6), by appropriately using the output ofthe four X linear encoder systems and the four Y linear encoder systemsdescribed above, obtains position information (hereinafter called “firstinformation”) on fine movement stage 22 (substrate P) in the X-axisdirection, the Y-axis direction, and the θz direction.

Here, with upward scale 72, measurable distance in the X-axis directionis set longer than the measurable distance in the Y-axis direction.Specifically, as is shown in FIG. 4, the length in the X-axis directionof upward scale 72 is around the same length as scale base 84, and isset around to a length that can cover a movable range in the X-axisdirection of fine movement stage 22. Meanwhile, the width direction(Y-axis direction) size (and spacing between a pair of heads 74 x and 74y adjacent in the Y-axis direction) of upward scale 72 is set to about alength so that the measurement beam from each of the heads 74 x and 74 ydoes not move off the grating surface (surface to be measured) of thecorresponding upward scale 72, even when fine movement stage 22 isfinely moved in the Y-axis direction with respect to upward scale 72.

Next, an operation of fine movement stage measurement system 76 (referto FIG. 6) will be described, using FIGS. 4 and 5. FIGS. 4 and 5 showsubstrate stage device 20 before and after fine movement stage 22 movesin long strokes in the X-axis and the Y-axis directions. FIG. 4 showsfine movement stage 22 in a state positioned almost at the center of themovable range in the X-axis and the Y-axis directions, and FIG. 5 showsfine movement stage 22 in a state positioned at the +X side stroke endof the movable range in the X-axis direction and also at the −Y sidestroke end in the Y-axis direction.

As it can be seen from FIGS. 4 and 5, regardless of the position in theY-axis direction of fine movement stage 22, the measurement beam fromeach of the heads 74 x and 74 y attached to fine movement stage 22 doesnot move off from the grating surface of upward scale 72 including thecase when fine movement stage 22 is finely moved in the Y-axisdirection. Also, when fine movement stage 22 moves in long strokes inthe X-axis direction as well, the measurement beam from each of thedownward heads 74 x and 74 y does not move off from the grating surfaceof upward scale 72.

Next, coarse movement stage measurement system 82 (refer to FIG. 6) willbe described. Coarse movement stage measurement system 82 of theembodiment, as it can be seen from FIGS. 1 and 4, has two downwardscales 78 (that is, a total of four downward scales 78) arrangedseparately in the X-axis direction on the +Y side and the −Y side ofprojection optical system 16 (refer to FIG. 1). Downward scale 78 isfixed to the lower surface of optical surface plate 18 a, via scale base92 (refer to FIG. 2). Scale base 92 is a plate shaped member extendingin the Y-axis direction, and the length in the Y-axis direction is setto around the same (actually slightly longer) as the movable distance offine movement stage 22 (that is, substrate P (not shown in FIG. 4)) inthe Y-axis direction.

Downward scale 78 is a plate shaped (strip shaped) member extending inthe Y-axis direction, and on its lower surface (a surface facing the −Zside (lower side)), a reflection type two-dimensional grating (so-calledgrating) is formed whose periodic direction is in two-axis directions(in the embodiment, X-axis and Y-axis directions) orthogonal to eachother, similarly to the upward scale 72 described above. Note that thegrating pitch of the diffraction grating that downward scale 78 has maybe the same as, or different from the grating pitch of the diffractiongrating that upward scale 72 has.

To each of the pair of scale bases 84 that Y coarse movement stage 24has, as is shown in FIG. 2, head base 96 is fixed via an arm member 94formed in an L shape when viewed from the X-axis direction. Head bases96, as is shown in FIG. 4, are arranged near the ends on the +X side andon the −X side of scale base 84. Each of the upward heads 80 x and 80 y,as is shown in FIG. 3, is fixed to the upper surface of head base 96.Accordingly, a total of four head bases 96 (and upward heads 80 x and 80y) can be moved in the Y-axis direction integrally with Y coarsemovement stage 24.

With coarse movement stage measurement system 82 (refer to FIG. 6) ofthe embodiment, as is shown in FIG. 3, two upward X heads 80 x and twoupward Y heads 80 y are arranged separately in the Y-axis direction forone head base 96. Each of the heads 80 x and 80 y irradiates thecorresponding downward scale 78 with a measurement beam, and alsoreceives light (here, a diffracted light) from downward scale 78. Lightfrom downward scale 78 is supplied to a detector not shown, and theoutput of the detector is supplied to main controller 100 (refer to FIG.6). Main controller 100 obtains relative movement amount of each of theheads 80 x and 80 y with respect to scale 78, based on the output of thedetector. As is described so far, in coarse movement stage measurementsystem 82 of the embodiment, with a total of eight upward X heads 80 xand the corresponding downward scale 78, eight X linear encoder systemsare structured, and also with a total of eight upward Y heads 80 y andthe corresponding downward scale 78, eight Y linear encoder systems arestructured. Main controller 100 (refer to FIG. 6), by appropriatelyusing the output of the eight X linear encoder systems and the eight Ylinear encoder systems described above, obtains position information(hereinafter called “second information”) on Y coarse movement stage 24in the X-axis direction, the Y-axis direction, and the θz direction.

Also, upward scale 72 fixed on scale base 84 and each of the upwardheads 80 x and 80 y integrally fixed to scale base 84 via head base 96are arranged, so that their mutual positional relation is to beinvariant and that the positional relation is to be known. Hereinafter,information related to relative positional relation between upward scale72 and each of the upward heads 80 x and 80 y integrally fixed theretowill be called “third information.” Note that while in the description,upward scale 72 and upward heads 80 x and 80 y were described to bearranged so that their the positional relation was to be invariant,liquid crystal exposure apparatus 10 may be equipped with a measurementsystem for measuring the positional relation between the two. The sameapplies to each embodiment that will be described below.

Main controller 100 (refer to FIG. 6) obtains position information onfine movement stage 22 (substrate P) within the XY plane with opticalsurface plate 18 a (projection optical system 16) serving as areference, based on the first to third information described above, andperforms position control of substrate P with respect to projectionoptical system 16 (illumination light IL), using substrate drive system60 (refer to FIG. 6) described above.

As is described, in substrate measurement system 70 of the embodiment,position information on Y coarse movement stage 24 which moves in longstrokes in the Y-axis direction is obtained by coarse movement stagemeasurement system 82 including downward scale 78 whose measurabledistance is longer in the Y-axis direction than that of the X-axisdirection (the Y-axis direction serving as the main measurementdirection), and position information on fine movement stage 22 whichmoves in long strokes in the X-axis direction is also obtained by finemovement stage measurement system. 76 including upward scale 72 whosemeasurable distance is longer in the X-axis direction than that of theY-axis direction (the X-axis direction serving as the main measurementdirection). That is, in coarse movement stage measurement system 82 andfine movement stage measurement system 76, the moving direction of eachencoder head (74 x, 74 y, 80 x, and 80 y) coincides with the mainmeasurement direction of the corresponding scales (72 and 78).

Also, position information on fine movement stage 22 (substrate P) ineach of the Z-axis, the θx, and the θy directions (hereinafter called“Z-tilt direction”) obtained by main controller 100 using a Z-tiltposition measurement system 98 (each refer to FIG. 6). While thestructure of Z-tilt position measurement system 98 is not limited inparticular, as an example, it is possible to use a measurement systemusing a displacement sensor attached to fine movement stage 22, as isdisclosed in U.S. Patent Application Publication No. 2010/0018950 andthe like.

Note that although it is not shown, substrate measurement system 70 alsohas a measurement system for obtaining position information on X coarsemovement stage 26. In the embodiment, since position information on finemovement stage 22 (substrate P) in the X-axis direction is obtained viaY coarse movement stage 24 with optical surface plate 18 a serving as areference, measurement accuracy of the X coarse movement stage 26 itselfdoes not have to be the same level as fine movement stage 22. Positionmeasurement of X coarse movement stage 26 may be performed, based on theoutput of fine movement stage measurement system 76 described above andthe output of the measurement system (not shown) which measures therelative position between X coarse movement stage 26 and fine movementstage 22, or may be performed using an independent measurement system.

In liquid crystal exposure apparatus 10 (refer to FIG. 1) structured inthe manner described above, loading of mask M onto mask stage device 14is performed by a mask loader (not shown), along with loading ofsubstrate P onto substrate holder 32 by a substrate loader (not shown),under the control of main controller 100 (refer to FIG. 6). Then,alignment measurement is executed using an alignment detection system(not shown) by main controller 100, and after the alignment measurementhas been completed, exposure operation of a step-and-scan method issequentially performed on a plurality of shot areas set on substrate P.Since this exposure operation is similar to the exposure of astep-and-scan method conventionally performed, a detailed descriptionthereabout is to be omitted. In the alignment measurement operation andthe exposure operation of the step-and-scan method, position informationon fine movement stage 22 is measured by substrate measurement system70.

With liquid crystal exposure apparatus 10 of the embodiment described sofar, since the position of fine movement stage 22 (substrate P) ismeasured using substrate measurement system 70 which includes an encodersystem, influence of air fluctuation is less than that of theconventional measurement using an optical interferometer system, whichallows position control of substrate P with high precision so that theexposure accuracy can be improved.

Also, since substrate measurement system 70 performs positionmeasurement of substrate P with downward scale 78 fixed to opticalsurface plate 18 a (apparatus main section 18) as a reference (viaupward scale 72), position measurement of substrate P can be performedwith projection optical system 16 substantially serving as a reference.This allows position control of substrate P to be performed withillumination light IL serving as a reference, which can improve exposureaccuracy.

Note that the structure of substrate measurement system 70 described sofar can be appropriately changed, as long as position information onfine movement stage 22 can be obtained at a desired accuracy in themovable range of fine movement stage 22 (substrate P).

That is, while a long scale having a length about the same as that ofscale base 84 was used as upward scale 72 in the embodiment above, thescale is not limited to this, and scales having a shorter length in theX-axis direction may be arranged at a predetermined spacing in theX-axis direction, similarly to the encoder system disclosed in U.S.Patent International Publication WO 2015/147319. In this case, since agap is formed in between a pair of scales adjacent in the X-axisdirection, by making the spacing in the X-axis direction of each of thepair of heads 74 x and 74 y adjacent in the X-axis direction wider thanthe gap described above, one of the heads 74 x and one of the heads 74 yshould be made to constantly face the scale. The same applies for therelation between downward scale 78 and upward heads 80 x and 80 y.

Also, while upward scale 72 was arranged on the +Y side and the −Y sideof fine movement stage 22, the arrangement is not limited to this, andthe scale may be arranged only on one side (the +Y side, or the −Yside). In the case only one upward scale 72 is arranged, and a pluralityof scales are arranged at a predetermined spacing (gap between scales)in the X-axis direction as is described above, the number andarrangement of each of the heads 74 x and 74 y should be set so that atleast two downward X heads 74 x (or downward Y heads 74 y) constantlyface the scale to allow position measurement of fine movement stage 22in the θz direction to be performed at all times. The same applies fordownward scale 78, and as long as position measurement of Y coarsemovement stage 24 in the X-axis, the Y-axis, and the θz direction can beperformed at all times, the number and arrangement of downward scale 78and upward heads 80 x and 80 y can be appropriately changed.

Also, while a two-dimensional diffraction grating whose periodicdirection is in the X-axis and the Y-axis directions were formed onupward scale 72 and downward scale 78, an X diffraction grating whoseperiodic direction is in the X-axis direction and a Y diffractiongrating whose periodic direction is in the Y-axis direction may beformed separately on scales 72 and 78. Also, while the two-dimensionaldiffraction grating in the embodiment had periodic directions in theX-axis and the Y-axis directions, if position measurement of substrate Pwithin the XY plane can be performed at a desired accuracy, the periodicdirection of the diffraction grating is not limited to this, and can beappropriately changed.

Also, Z-tilt position information on substrate P may be measured byattaching a displacement sensor facing downward to head base 88, andalso using the sensor with scale base 84 (or a reflection surface ofupward scale 72) serving as a reference. Also, at least three heads ofthe plurality of downward heads 74 x and 74 y may serve astwo-dimensional heads (so-called XZ heads or YZ heads) that can performmeasurement in a vertical direction along with position measurement in adirection parallel to the horizontal plane, and Z-tilt positioninformation on substrate P may be obtained by the two-dimensional headsusing the grating surface of upward scale 72. Similarly, Z-tilt positioninformation on Y coarse movement stage 24 may be measured with scalebase 92 (or a downward scale 78) serving as a reference. As the XZ heador the YZ head, an encoder head of a structure similar to thedisplacement sensor head disclosed in, for example, U.S. Pat. No.7,561,280, can be used.

Second Embodiment

Next, a liquid crystal exposure apparatus according to a secondembodiment will be described, using FIGS. 7 to 10. Since the structureof the liquid crystal exposure apparatus according to the secondembodiment is roughly the same as that of the first embodiment describedabove, except for the point that the structure of a substrate stagedevice 220 (including the measurement system) is different, only thedifferent points will be described below, and for elements having thesame structure or function as the first embodiment described above willhave the same reference code as the first embodiment and the descriptionthereabout will be omitted.

Substrate stage device 220 according to the second embodiment has afirst system including a first movable body (here, substrate holder 32),and a second system including a second movable body (here, X coarsemovement stage 222). FIGS. 9 and 10 are planar views showing only thesecond system and the first system.

As is shown in FIG. 9, X coarse movement stage 222 is mounted in afreely movable state in the X-axis direction on a pair of base frames224 installed on floor F (refer to FIG. 8), via a mechanical linearguide device (refer to FIG. 8), similarly to Y coarse movement stage 24(refer to FIG. 1) in the first embodiment described above. At both endsnear the edge in the X-axis direction of X coarse movement stage 222,

Y stators are attached. Y stator 226 consists of a member extending inthe Y-axis direction, and at both ends near the edge in the longitudinaldirection, X movers 228 are attached. Each X mover 228 works togetherwith X stator 230 (not shown in FIG. 8) and structures an X linearmotor, and X coarse movement stage 222 is moved in predetermined longstrokes in the X-axis direction by a total of four X linear motors. Xstators 230 are installed on floor F in a state physically separatedfrom apparatus main section 18 (refer to FIG. 1).

As is shown in FIG. 8, substrate holder 32 is mounted on a Y beam guide232 via a Y table 234. Y beam guide 232, as is shown in FIG. 10,consists of a member extending in the Y-axis direction, and on the lowersurface at both ends near the edge in the longitudinal direction, Xslide members 236 are attached. Each X slide member 236 engages in afreely movable state in the X-axis direction with an X guide member 238fixed to lower mount section 18 c (refer to FIG. 8). Also, at both endsnear the edge in the longitudinal direction of Y beam guide 232, Xmovers 240 are attached. Each X mover 240 works together with X stator230 (refer to FIG. 9) and structures an X linear motor, and Y beam guide232 is moved in predetermined long strokes in the X-axis direction by atotal of two X linear motors.

As is shown in FIG. 8, Y table 234 consists of a member with a crosssectional surface of an inverted U-shape, and Y beam guide 232 isinserted therein via air bearings 242 attached freely swingable to apair of opposite surfaces.

Also, Y table 234, by blowing out pressurized gas onto the upper surfaceof Y beam guide 232 from air bearings (not shown), is mounted on Y beamguide 232 via a slight gap. This allows Y table 234 to be freely movablewith long strokes in the Y-axis direction and also to be freelyrotatable at a fine angle in the θz direction, with respect to Y beamguide 232. Also, Y table 234, in the X-axis direction, moves integrallywith Y beam guide 232 by rigidity of a gas film formed by air bearings242 described above. At both ends near the edge in the X-axis directionof Y table 234, Y movers 244 are attached. Y movers 244 work with Ystators 226 and structure Y linear motors, and Y table 234 is moved inpredetermined long strokes along Y beam guide 232 in the Y-axisdirection by a total of two Y linear motors as well as being finelymoved in the θz direction.

In substrate stage device 220, when X coarse movement stage 222 is movedin the X-axis direction by the four X linear motors (X movers 228 and Xstators 230), the two Y stators 226 attached to X coarse movement stage222 also move in the X-axis direction. The main controller (not shown)moves Y beam guide 232 in the X-axis direction by the two X linearmotors (X movers 240 and X stators 230) so that a predeterminedpositional relation is maintained with X coarse movement stage 222. Thismoves Y table 234 (that is, substrate holder 32) in the X-axis directionintegrally with Y beam guide 232 . That is, X coarse movement stage 222is a member that can move while a position in the X-axis direction withsubstrate holder 32 stays within a predetermined range. Also,concurrently with, or independently from the movement of substrateholder 32 described above in the X-axis direction, the main controllerappropriately moves substrate holder 32 in the Y-axis direction and theθz direction, using the two Y linear motors (Y movers 244 and Y stators226).

Next, a substrate measurement system 250 according to the secondembodiment will be described. With substrate measurement system 250,while the extending direction (the direction wider in the measurementrange) of each of an upward scale 252 and a downward scale 254 isdifferent by 90 degrees around the Z-axis from the first embodiment, theconcept of the measurement system is roughly the same as that of thefirst embodiment described above, on the point that position informationon the first movable body (in this case, substrate holder 32) isobtained with optical surface plate 18 a (refer to FIG. 1) serving as areference, via the second movable body (in this case, X coarse movementstage 222).

That is, as is shown in FIG. 7, on the upper surface of each of the pairof Y stators 226, upward scale 252 extending in the Y-axis direction isfixed. Also, to both side surfaces in the X-axis direction of substrateholder 32, a pair of head bases 256 is fixed, arranged apart in theY-axis direction.

To head bases 256, similarly to the first embodiment described above,two downward X heads 74 x and two downward Y heads 74 y (refer to FIG.10) are attached so that the heads face the corresponding upward scales252. Position information on substrate holder 32 within the XY planewith respect to X coarse movement stage 222 is obtained by the maincontroller (not shown), using a total of eight X linear encoders and atotal of eight Y linear encoders.

Also, at both ends near the edge in the Y-axis direction of Y stator226, a head base 258 is fixed. To head base 258, similarly to the firstembodiment described above, two upward X heads 80 x and two upward Yheads 80 y (refer to FIG. 9) are attached to face the correspondingdownward scale 254 fixed to the lower surface of optical surface plate18 a (refer to FIG. 1). The relative positional relation between upwardscale 252 and each of the heads 80 x and 80 y is known. Positioninformation on X coarse movement stage 222 within the XY plane withrespect to optical surface plate 18 a is obtained by the main controller(not shown), using a total of eight X linear encoders and a total ofeight Y linear encoders.

Note that with substrate measurement system 250 of the secondembodiment, while two upward scales 252 are attached to X coarsemovement stage 222 and four downward scales 254 are attached to opticalsurface plate 18 a (refer to FIG. 1), the number and arrangement of eachof the scales 252 and 254 are not limited to this, and can beappropriately increased or decreased. Similarly, the number andarrangement of each of the heads 74 x, 74 y, 80 x, and 80 y facing eachof the scales 252 and 254 are not limited to this, and can beappropriately increased or decreased. The same also applies to the thirdto seventeenth embodiments that will be described below.

Third Embodiment

Next, a liquid crystal exposure apparatus according to a thirdembodiment will be described, using FIGS. 11 to 14. Since the structureof the liquid crystal exposure apparatus according to the thirdembodiment is roughly the same as that of the second embodimentdescribed above, except for the point that the structure of a substratestage device 320 (including the measurement system) is different, onlythe different points will be described below, and for elements havingthe same structure or function as the second embodiment described abovewill have the same reference code as the second embodiment and thedescription thereabout will be omitted.

Substrate stage device 320 according to the third embodiment has a firstsystem including substrate holder 32 (refer to FIG. 14), and a secondsystem including X coarse movement stage 222 (refer to FIG. 13),similarly to the second embodiment described above. Since the structureof substrate holder 32 and X coarse movement stage 222 (including thedrive systems) is the same as that of the second embodiment describedabove, the description thereabout will be omitted.

A substrate measurement system 350 of the third embodiment is alsoconceptually similar to the first and the second embodiments describedabove, and position information on the first movable body (in this case,substrate holder 32) is obtained with optical surface plate 18 a (referto FIG. 1) serving as a reference, via the second movable body (in thiscase, Y beam guide 232). Y beam guide 232 is a member that can movewhile a position in the X-axis direction with substrate holder 32 stayswithin a predetermined range. Next, the details of substrate measurementsystem 350 will be described.

As is shown in FIG. 14, an upward scale 352 is fixed to the uppersurface of Y beam guide 232. Also, to both side surfaces in the Y-axisdirection of Y table 234 (not shown in FIG. 14, refer to FIG. 12) headbases 354 are fixed. To each head base 354, similarly to the first andthe second embodiments described above, two downward X heads 74 x andtwo downward Y heads 74 y are attached so that the heads face thecorresponding upward scale 352. Position information on substrate holder32 within the XY plane with respect to Y beam guide 232 is obtained bythe main controller (not shown), using a total of four X linear encodersand a total of four Y linear encoders.

Also, at both ends near the edge in the Y-axis direction of Y beam guide232, a head base 356 is fixed. To head base 356, similarly to the firstembodiment described above, two upward X heads 80 x and two upward Yheads 80 y are attached to face the corresponding downward scale 358fixed to the lower surface of optical surface plate 18 a (refer to FIG.1). The relative positional relation between upward scale 352 and eachof the heads 80 x and 80 y attached to head base 356 is known. Positioninformation on Y beam guide 232 within the XY plane with respect tooptical surface plate 18 a is obtained by the main controller (notshown), using a total of four X linear encoders and a total of four Ylinear encoders. The number of upward scales 352 and downward scales 358in the third embodiment is less than and the structure more simple thanthat of the second embodiment.

Fourth Embodiment

Next, a liquid crystal exposure apparatus according to a fourthembodiment will be described, using FIGS. 15 to 18. Since the structureof the liquid crystal exposure apparatus according to the fourthembodiment is roughly the same as that of the second embodimentdescribed above, except for the point that the structure of a substratestage device 420 (including the measurement system) is different, onlythe different points will be described below, and for elements havingthe same structure or function as the second embodiment described abovewill have the same reference code as the second embodiment and thedescription thereabout will be omitted.

Substrate stage device 420 according to the fourth embodiment has afirst system including substrate holder 32 (refer to FIG. 18), and asecond system including X coarse movement stage 222 (refer to FIG. 17),similarly to the second embodiment described above.

As is shown in FIG. 16, to the lower surface of X coarse movement stage222, an X mover 422 is fixed. X mover 422 structures an X linear motor;working together with an X stator 424 integrally attached to the pair ofbase frames 224 to move X coarse movement stage 222 in predeterminedlong strokes in the X-axis direction. At both ends near the edge in theX-axis direction of X coarse movement stage 222, XY stators 426 areattached.

Y beam guide 232 is mechanically connected to X coarse movement stage222 by four connecting members 428 (refer to FIG. 15). The structure ofconnecting members 428 is similar to that of connecting members 46 and54 (refer to FIG. 2). With this structure, when X coarse movement stage222 is moved in the X-axis direction by the X linear motor, Y beam guide232 is pulled by X coarse movement stage 222, and moves in the X-axisdirection integrally with X coarse movement stage 222.

On Y beam guide 232, a Y table 430 is mounted in a non-contact manner.On Y table 430, substrate holder 32 is fixed. At both ends near the edgein the X-axis direction of Y table 430, XY movers 432 are attached. XYmovers 432 work together with XY stators 426 to structure an XY 2-DOFmotor, and Y table 430 is moved in predetermined long strokes in theY-axis direction by a total of two XY 2-DOF motors, and is also finelymoved in the X direction and the θz direction. Also, when X coarsemovement stage 222 (and Y beam guide 232) moves in long strokes in theX-axis direction, the main controller (not shown), using the total oftwo XY 2-DOF motors, makes thrust act in the X-axis direction so that Ytable 430 (that is, substrate holder 32) maintains a predeterminedpositional relation in the X-axis direction with Y beam guide 232. Thatis, X coarse movement stage 222 is a member that can be moved so thatthe position in the X-axis direction with substrate holder 32 stayswithin a predetermined range. Note that different from the secondembodiment described above, Y table 430 does not have air bearings 242(refer to FIG. 8) that are swingable, and Y beam guide 232 of theembodiment, and Y beam guide 232 in the embodiment actually does notguide Y table 430 moving in the Y-axis direction.

A substrate measurement system 450 of the fourth embodiment is alsoconceptually similar to the first to the third embodiments describedabove, and position information on the first movable body (in this case,substrate holder 32) is obtained with optical surface plate 18 a (referto FIG. 1) serving as a reference, via the second movable body (in thiscase, X coarse movement stage 222). Next, the details of substratemeasurement system 450 will be described.

As is shown in FIG. 17, of the pair of XY stators 426, an upward scale452 is fixed to the upper surface of one of the XY stators 426 (here,the −X side). Also, as is shown in FIG. 18, a pair of head bases 454 isfixed to the side surface n the −X side of substrate holder 32, in astate arranged apart in the Y-axis direction. To each head base 454,similarly to the first to the third embodiments described above, twodownward X heads 74 x and two downward Y heads 74 y are attached so thatthe heads face the corresponding upward scale 452 (refer to FIG. 16).Position information on substrate holder 32 within the XY plane withrespect to X coarse movement stage 222 is obtained by the maincontroller (not shown), using a total of four X linear encoders and atotal of four Y linear encoders.

Also, to XY stator 426 on the −X side, a pair of head bases 456 isfixed, arranged apart in the Y-axis direction. To head base 456,similarly to the first embodiment described above, two upward X heads 80x and two upward Y heads 80 y are attached (refer to FIG. 15) to facethe corresponding downward scale 458 fixed to the lower surface ofoptical surface plate 18 a (refer to FIG. 1). The relative positionalrelation between upward scale 452 and each of the heads 80 x and 80 yattached to head base 456 is known. Position information on X coarsemovement stage 222 within the XY plane with respect to optical surfaceplate 18 a is obtained by the main controller (not shown), using a totalof four X linear encoders and a total of four Y linear encoders. Notethat upward scale 452 may be attached only to one of, or to both of thepair of XY stators 426. In the case of attaching upward scale 452 to XYstator 426 on the +X side, head bases 454 and 456, and downward scale254 may be arranged additionally, corresponding to upward scale 452.

Fifth Embodiment

Next, a liquid crystal exposure apparatus according to a fifthembodiment will be described, using FIGS. 19 to 22. The structure of theliquid crystal exposure apparatus according to the fifth embodiment isroughly the same as that of the fourth embodiment, except for the pointthat the structure of a substrate measurement system. 550 is different.Also, the structure of substrate measurement system 550 is roughly thesame as substrate measurement system 350 (refer to FIG. 11 and the like)of the third embodiment described above. Hereinafter, only the differentpoints will be described, and for elements having the same structure orfunction as the third or the fourth embodiment described above will havethe same reference code as the third or the fourth embodiments, and thedescription thereabout will be omitted.

The structure of substrate stage device 520 (excluding the measurementsystem) according to the fifth embodiment is substantially the same assubstrate stage device 420 (refer to FIG. 15) according to the fourthembodiment described above. That is, substrate stage device 520 has afirst system including substrate holder 32 (refer to FIG. 22), and asecond system including X coarse movement stage 222 (refer to FIG. 21),and X coarse movement stage 222 moves integrally with Y beam guide 232in the X-axis direction. Y table 430, to which substrate holder 32 isfixed, is moved in long strokes in the Y-axis direction with respect toX coarse movement stage 222 by two 2-DOF motors, and is also finelymoved in the X direction and the θz direction. While the conventionalcoarse movement stage was moved based on measurement results of anencoder with low measurement accuracy, in the embodiment, it is possibleto move and control X coarse movement stage 222 based on measurementresults of a two-dimensional encoder with high accuracy. Accordingly,while positioning with higher precision than that of the conventionalfine movement stage becomes possible, X coarse movement stage 222 doesnot necessarily have the responsiveness that the fine movement stage (inthe embodiment, substrate holder 32) has. Therefore, the X position ofsubstrate holder 32 should be controlled to move while performing anaccurate positioning at a constant speed, regardless of the position ofX coarse movement stage 222 during scanning operation. Therefore,substrate holder 32 is to be finely moved relatively in the X-axisdirection with respect to X coarse movement stage 222 which moves whileperforming rough positioning control with low responsiveness. On thisoperation, when X coarse movement stage 222 accelerates, a reading errormay occur of the encoder with respect to upward scale 452. Accordingly,X coarse movement stage 222 should be controlled rather to perform loosepositioning (low responsiveness). Of each of the embodiments that willbe described below, the coarse movement stage should be controlledsimilarly in an embodiment where coarse movement stage moves on scanningoperation.

Also, the structure of substrate measurement system 550 according to thefifth embodiment is substantially the same as that of substratemeasurement system 350 (refer to FIG. 11) according to the thirdembodiment, and position information on the first movable body (in thiscase, substrate holder 32) is obtained with optical surface plate 18 a(refer to FIG. 1) serving as a reference, via the second movable body(in this case, Y beam guide 232). Specifically, to the pair of headbases 354 fixed to Y table 430 (refer to FIG. 20), two downward X heads74 x and two downward Y heads 74 y are attached (each refer to FIG. 22)to face upward scale 352 fixed to the upper surface of Y beam guide 232,and position information on substrate holder 32 within the XY plane withrespect to Y beam guide 232 is obtained by the main controller (notshown), using a total of four X linear encoders and a total of four Ylinear encoders . Also, a pair of head bases 356 fixed to Y beam guide232, two upward X heads 80 x and two upward Y heads 80 y are attached(refer to FIG. 19) to face the corresponding downward scale 358 fixed tothe lower surface of optical surface plate 18 a (refer to FIG. 1).Position information on Y beam guide 232 within the XY plane withrespect to optical surface plate 18 a is obtained by the main controller(not shown), using a total of four X linear encoders and a total of fourY linear encoders.

Sixth Embodiment

Next, a liquid crystal exposure apparatus according to a sixthembodiment will be described, using FIGS. 23 to 27. Since the structureof the liquid crystal exposure apparatus according to the sixthembodiment is roughly the same as that of the first embodiment describedabove, except for the point that the structure of a substrate stagedevice 620 and its measurement system is different, only the differentpoints will be described below, and for elements having the samestructure or function as the first embodiment described above will havethe same reference code as the first embodiment and the descriptionthereabout will be omitted.

As is shown in FIG. 23, substrate stage device 620 is equipped with; asubstrate measurement system 680 including a first movable body (here,substrate holder 622) and a second movable body (here, measurement table624), a substrate table 626, an X coarse movement stage 628 and thelike.

As is shown in FIG. 24, substrate holder 622 is a frame shaped (pictureframe shape) member with a rectangular shape in a planar view that is acombination of a pair of members extending in the Y-axis direction and apair of members extending in the X-axis direction, and substrate P isarranged in an opening of substrate holder 622. Four suction pads 630protrude from the inner walls of substrate holder 622, and substrate Pis mounted on these suction pads 630. Each suction pad 630 holds bysuction a non-exposure area (in the embodiment, an area near the fourcorners) set at an outer periphery section on the lower surface ofsubstrate P.

Of substrate P, an exposure area (an area other than the outer peripherysection) including the center is supported from below in a non-contactmanner by substrate table 626. While substrate holder 32 (refer to FIG.2 and the like) in the first to fifth embodiments performed flatnesscorrection by holding substrate P by suction, with substrate table 626according to the sixth embodiment, flatness correction of substrate P isperformed in a non-contact manner by concurrently performing blow out ofpressurized gas to the lower surface of substrate P and suction of gasbetween substrate P and the upper surface of substrate table 626. Also,substrate holder 622 and substrate table 626 are arranged physicallyseparate. Accordingly, substrate P held by substrate holder 622 is in astate relatively movable within the XY plane with respect to substratetable 626, integrally with substrate holder 622. To the lower surface ofsubstrate table 626, as is shown in FIG. 23, a stage main section 632 isfixed, similarly to that of the first embodiment described above.

X coarse movement stage 628, which is a member used to move substratetable 626 in the X-axis direction with long strokes, is mounted in astate freely movable in the X-axis direction on a pair of base frames634 installed on floor F in a state physically separate from lower mountsection 18 c, via a mechanical linear guide device 636. X coarsemovement stage 628 is moved in long strokes in the X-axis direction onthe pair of base frames 634 by an actuator (such as a linear motor, aball screw device or the like).

At both ends near the edge in the X-axis direction of X coarse movementstage 628, Y stators 638 are fixed (one of the stators not shown in FIG.23). Y stators 638 work together with Y movers 640 to structure a Ylinear motor. Y movers 640 are mechanically restricted to move in theX-axis direction integrally when Y stators 638 move in the X-axisdirection. To Y movers 640, stators 644 are attached that structure XY2-DOF motors together with movers 642 (refer to FIG. 24) attached tosubstrate holder 622.

As is shown in FIG. 25, substrate table 626 is mechanically connected toX coarse movement stage 628 (not shown in FIG. 25) (to Y stators 638 inFIG. 25) via a plurality of connecting members 646, via stage mainsection 632 (not shown in FIG. 25, refer to FIG. 23). The structure ofconnecting members 646 is similar to that of connecting members 46 and54 (refer to FIG. 2). With this structure, when X coarse movement stage628 moves in long strokes in the X-axis direction, substrate table 626is pulled by X coarse movement stage 628, and is moved in the X-axisdirection integrally with X coarse movement stage 628. In the first tothe fifth embodiments described above, while substrate holder 32 movesin long strokes in the X-axis and the Y-axis directions with respect toprojection optical system 16 (refer to FIG. 5 and the like), substratetable 626 in the sixth embodiment is structured movable in long strokesin only the X-axis direction, and is to be immovable in the Y-axisdirection. Note that in FIG. 25, to facilitate understanding, while Ystators 638, Y movers 640, and stators 644 are arranged planar (the sameheight position) different from those of FIG. 23, by making the heightof Y stators 638 equal to the height position of substrate holder 622,an arrangement like the one shown in FIG. 25 is actually possible.

Referring back to FIG. 23, stage main section 632 is supported frombelow by weight canceling device 42 arranged in an opening (not shown)formed in the center of X coarse movement stage 628, via apseudospherical bearing device (not shown in FIG. 23 being arranged inthe depth of the page surface, such as behind Y mover 640) similar tothat of the first embodiment described above. The structure of weightcanceling device 42, which is similar to that of the device in the firstembodiment described above, is connected to X coarse movement stage 628via a connecting member (not shown), and moves in long strokes in onlythe X-axis direction integrally with X coarse movement stage 628. Weightcanceling device 42 is mounted on an X guide 648. Since weight cancelingdevice 42 in the embodiment is structured to move only in the X-axisdirection, X guide 648 is fixed to lower mount section 18 c, differentfrom Y step guide 44 (refer to FIG. 2) in the first embodiment describedabove. The point that stage main section 632 is finely moved in each ofthe Z-axis, the θx, and the θy directions by a plurality of linear coilmotors (hidden in the depth side of the page surface of Y stators 638 inFIG. 23) is similar to that of the first embodiment described above.

Also, to both side surfaces in the Y-axis direction of stage mainsection 632, a plurality of air guides 652 is attached via supportmember 650. Air guides 652, as is shown in FIG. 25, is a member having arectangular shape in a planar view, and in the embodiment, four each ofthe air guides are arranged on the +Y side and the −Y side of substratetable 626. The length in the Y-axis direction of a guide surface formedby the four air guides 652 is set equal to that of substrate table 626,and the height position of the guide surface is set equivalent to (orslightly lower than) the upper surface of substrate table 626.

With substrate stage device 620 (refer to FIG. 23), when X coarsemovement stage 628 moves in long strokes in the X-axis direction at thetime of scanning exposure and the like, substrate table 626 (and theplurality of air guides 652) is pulled by X coarse movement stage 628,and moves integrally in long strokes in the X-axis direction. Also, by Ystators 638 fixed to X coarse movement stage 628 moving in the X-axisdirection, stators 644 (refer to FIG. 25) of the 2-DOF motors attachedto Y mover 640 also move in the X-axis direction. The main controller(not shown) controls the 2-DOF motors so that position in the X-axisdirection of substrate table 626 and substrate holder 622 is within apredetermined range, and gives substrate holder 622 thrust in the X-axisdirection. Also, the main controller controls the 2-DOF motors andfinely moves substrate holder 622 appropriately in the X-axis, theY-axis, and the θz directions with respect to substrate table 626. As isdescribed, in the embodiment, substrate holder 622 has a function as aso-called fine movement stage.

Meanwhile, in the case substrate P has to be moved in the Y-axisdirection at the time of movement between shot areas (exposure areas),as is shown in FIG. 27, the main controller moves substrate holder 622in the Y-axis direction with respect to substrate table 626, by making Ymover 640 move in the Y-axis direction by the Y linear motor and alsomaking thrust in the Y-axis direction act on substrate holder 622 usingthe 2-DOF motors. Of substrate P, in the area (exposure area) where themask pattern is projected via projection optical system 16 (refer toFIG. 23), size in the Y-axis direction of substrate table 626 is set sothat flatness correction is performed by substrate table 626 at alltimes. Each air guide 652 is arranged so that relative movement in theY-axis direction of substrate holder 622 and substrate table 626 is notdisturbed (does not come into contact with substrate holder 622). Eachair guide 652, by blowing out pressurized gas to the lower surface ofsubstrate P, works together with substrate table 626 to support frombelow portions of substrate P that protrude from substrate table 626.Note that each air guide 652 is different from substrate table 626 anddoes not perform flatness correction on substrate P. In substrate stagedevice 620, as is shown in FIG. 27, scanning exposure is performed bysubstrate table 626 and substrate holder 622 being moved in the X-axisdirection with respect to projection optical system 16 (refer to FIG.23), in a state where substrate P is supported by substrate table 626and air guides 652. Note that air guides 652 may, or may not be moved inthe X-axis direction integrally with stage main section 632. In the caseair guides 652 are not moved in the X-axis direction, the size in theX-axis direction should be about the same as the moving range ofsubstrate Pin the X-axis direction. This can prevent a part of an areaof the substrate that is not supported by substrate table 626 from beingunsupported.

Next, a structure and operation of substrate measurement system 680according to the sixth embodiment will be described. In the firstembodiment (refer to FIG. 2) described above, while position informationon the first movable body (fine movement stage 22 in the firstembodiment) was obtained via Y coarse movement stage 24 which is amember for moving fine movement stage 22 with optical surface plate 18 aserving as a reference, in the sixth embodiment (refer to FIG. 23),position information on the first movable body (in this case, substrateholder 622) is obtained via a second movable body (in this case,measurement table 624) arranged independently from substrate holder 622with optical surface plate 18 a serving as a reference. In the sixthembodiment, while measurement table 624 is arranged; two on the +Y side,and two on the −Y side (a total of four) of projection optical system 16placed apart in the X-axis direction (refer to FIGS. 23, 26 and thelike), the number and arrangement of measurement table 624 can beappropriately changed, and is not limited to this.

Measurement table 624, as is shown in FIG. 23, is moved in predetermined(equivalent to the movable distance of substrate holder 622 in theY-axis direction) strokes in the Y-axis direction by a Y linear actuator682 fixed in a state suspended from the lower surface of optical surfaceplate 18 a. The type of Y linear actuator 682 is not limited inparticular, and a linear motor, a ball screw device, or the like can beused.

Similarly to head base 96 (refer to FIGS. 2, 3 and the like) of thefirst embodiment, on the upper surface of each measurement table 624,two upward X heads 80 x and two upward Y heads 80 y are attached, as isshown in FIG. 26.

Also, as is shown in FIG. 23, to the lower surface of optical surfaceplate 18 a, downward scales 684 extending in the Y-axis directioncorresponding to each measurement table 624 (that is, four) are fixed(refer to FIG. 26), similarly to downward scales 78 (refer to FIGS. 2, 3and the like) in the first embodiment described above. Downward scales684 have two-dimensional diffraction gratings on their lower surfaces sothat the measurement range in the Y-axis direction of measurement table624 becomes wider (longer) than the measurement range in the X-axisdirection. In the embodiment, the two upward X heads 80 x that eachmeasurement table 624 has and the corresponding downward scales 684(fixed scales) structure two X linear encoder systems, and the twoupward Y heads 80 y that each measurement table 624 has and thecorresponding downward scales 684 (fixed scales) structure two Y linearencoder systems.

The main controller (not shown), as is shown in FIG. 27, controlsposition of each measurement table 624 in the Y-axis direction, so thatthe position in the Y-axis direction with respect to substrate holder622 stays within a predetermined range on moving substrate holder 622 inlong strokes in the Y-axis direction. Accordingly, the total of fourmeasurement tables 624 substantially performs the same operation. Notethat the four measurement tables 624 do not necessarily have to movestrictly in synchronization with one another, and also does notnecessarily have to move strictly in synchronization with substrateholder 622. The main controller obtains position information on eachmeasurement table 624 in the X-axis direction, the Y-axis direction, andthe θz direction independently, appropriately using the output of thetwo X linear encoder systems and the two Y linear encoder systems.

Referring back to FIG. 26, to the lower surface of the two measurementtables 624 on the +Y side, downward scales 686 extending in the X-axisdirection are attached (refer to FIG. 23). That is, the two measurementtables 624 work together to suspend and support downward scales 686.Also to the lower surface of the two measurement tables 624 on the −Yside, downward scales 686 extending in the X-axis direction aresimilarly attached. Downward scales 686 have two-dimensional diffractiongratings on their lower surfaces so that the measurement range in theX-axis direction of substrate holder 622 becomes wider (longer) than themeasurement range in the Y-axis direction. The relative positionalrelation between upward heads 80 x and 80 y and downward scales 686fixed to measurement table 624 is known.

As is shown in FIG. 24, to the upper surface of substrate holder 622,two head bases 688 are fixed, corresponding to a total of two downwardscales 684 (refer to FIG. 26). Head bases 688 are arranged on the +Yside and the −Y side of substrate P sandwiching the center part ofsubstrate P, in a state where substrate P is held on substrate holder622.

To the upper surface of head bases 688, two upward X heads 80 x and twoupward Y heads 80 y are attached. As is described above, substrateholder 622 and each measurement table 624 (that is, the two downwardscales 686) are controlled so that the positions in the Y-axis directionstays within a predetermined range. Specifically, with each measurementtable 624, the position in the Y-axis direction is controlled so thatmeasurement beams from each of the heads 80 x and 80 y attached tosubstrate holder 622 do not move off from the grating surfaces ofdownward scales 686. That is, substrate holder 622 and each measurementtable 624 move in the same direction roughly at the same speed so thatthe state of head bases 688 facing downward scales 686 is maintained atall times.

As is described, in the sixth embodiment, the four upward X heads 80 xthat substrate holder 622 has and the corresponding downward scales 686(movable scales) structure four X linear encoder systems, and the fourupward Y heads 80 y that substrate holder 622 has and the correspondingdownward scales 686 (movable scales) structure four Y linear encodersystems. The main controller (not shown) obtains position information onsubstrate holder 622 within the XY plane with respect to the total offour measurement tables 624, based on the output of the four X linearencoder systems and the four Y linear encoder systems described above.The main controller obtains position information on substrate holder 622(substrate P) with optical surface plate 18 a serving as a reference,based on position information (first information) on substrate holder622 with respect to each measurement table 624, position information(second information) on each measurement table 624 with respect tooptical surface plate 18 a, and position information (third information)on upward heads 80 x and 80 y and downward scales 686 in eachmeasurement table 624.

Seventh Embodiment

Next, a liquid crystal exposure apparatus according to a seventhembodiment will be described, using FIGS. 28 to 31.

Since the structure of the liquid crystal exposure apparatus accordingto the seventh embodiment is roughly the same as that of the sixthembodiment described above, except for the point that the structure of asubstrate stage device 720 and its measurement system is different, onlythe different points will be described below, and for elements havingthe same structure or function as the sixth embodiment described abovewill have the same reference code as the sixth embodiment and thedescription thereabout will be omitted.

Also in the seventh embodiment, substrate stage device 720 is equippedwith a substrate measurement system 780 and the like; including a firstmovable body (here, a pair of substrate holders 722), and a secondmovable body (here, measurement table 624).

In the sixth embodiment (refer to FIG. 26 and the like), while substrateholder 622 was formed in a rectangular frame shape that surrounds theentire outer periphery of substrate P, the pair of substrate holders 722according to the seventh embodiment is physically separated and differson the point that one of the substrate holders 722 holds the end nearthe +X side of substrate P by suction, and the other substrate holder722 holds the end near the −X side of substrate P by suction. Since thestructure and function of substrate table 626, and the drive system formoving substrate table 626 is the same as those of the sixth embodimentdescribed above, the description thereabout will be omitted.

As is shown in FIG. 29, each substrate holders 722 has a suction pad 726that holds the center in the Y-axis direction of substrate P from below.Note that since a measurement plate 728 is attached to the upper surfaceof substrate holder 722 on the −X side, the length in the Y-axisdirection is set longer than substrate holder 722 on the +X side,however, the function to hold substrate P, position control operationand the like of substrate P is common in the pair of substrate holders722, therefore, in the embodiment, for convenience, the pair ofsubstrate holders 722 will be described having a common reference code.On measurement plate 728, an index is formed that is used forcalibration and the like relating to optical properties (scaling, shift,rotation and the like) of projection optical system 16 (refer to FIG.1).

Each substrate holder 722 is finely moved by 3-DOF motors structured bystators 730 that Y mover 640 has (each refer to FIG. 30) and movers 732that each substrate holder 722 has (each refer to FIG. 29), in the X,the Y, and the θz directions with respect to the corresponding Y mover640. In the embodiment, as the 3-DOF motor, while a combination of two Xlinear motors and one Y linear motor is used, the structure of the 3-DOFmotor is not limited in particular, and may be appropriately changed. Inthe seventh embodiment, while each substrate holder 722 is movedindependently with each other by the 3-DOF motor, the movement itself ofsubstrate P is similar to the sixth embodiment described above.

Referring back to FIG. 28, each substrate holder 722 is supported frombelow in a non-contact manner by an air guide 734 extending in theY-axis direction (refer to FIG. 31 for substrate holder 722 on the −Xside). The height position of the upper surface of air guide 734is setlower than the height position of the upper surface of substrate table626 and air guides 652. The length of air guide 734 is set to around thesame (or slightly longer than) the movable distance of substrate holders722 in the Y-axis direction. Air guide 734 is also fixed to stage mainsection 632 similarly to air guides 652, and moves in long strokes inthe X-axis direction integrally with stage main section 632. Note thatair guide 734 may be applied to substrate stage device 620 in the sixthembodiment described above.

Next, substrate measurement system 780 according to the seventhembodiment will be described. Substrate measurement system 780 accordingto the seventh embodiment is roughly the same conceptually as substratemeasurement system 680 (refer to FIG. 26) according to the sixthembodiment described above, except for the point that the arrangement ofheads on the substrate P side, the number and arrangement of measurementtable 624 and the like are different. That is, in substrate measurementsystem 780, position information on the first movable body (in thiscase, each substrate holder 722) is obtained via measurement table 624with optical surface plate 18 a serving as a reference. The details willbe described below.

The structure of measurement table 624 that substrate measurement system780 has is the same as that of the sixth embodiment described aboveexcept for the arrangement. In the sixth embodiment, as is shown in FIG.23, while measurement tables 624 were arranged on the +Y side and the −Yside of projection optical system 16, with measurement tables 624according to the seventh embodiment, as is shown in FIG. 28, theposition in the Y-axis direction overlaps with projection optical system16, and one measurement table 624 (refer to FIG. 28) is arranged on the+X side of projection optical system 16, and the other measurement table624 (not shown in FIG. 28) is arranged on the −X side of projectionoptical system 16 (refer to FIG. 31). Also in the seventh embodiment,similarly to the sixth embodiment described above, measurement tables624 are moved in predetermined strokes in the Y-axis direction by Ylinear actuators 682. Also, position information on each measurementtable 624 within the XY plane is obtained independently by the maincontroller (not shown), using an encoder system structured by upwardheads 80 x and 80 y (refer to FIG. 31) attached to measurement table 624and the corresponding downward scale 684 fixed to the lower surface ofoptical surface plate 18 a.

To each of the lower surfaces of the two measurement tables 624, adownward scale 782 is fixed (refer to FIG. 31). That is, in the sixthembodiment described above (refer to FIG. 27), while one downward scale686 was suspended and supported by two measurement tables 624, in theseventh embodiment, one downward scale 782 is suspended and supported byone measurement table 624. Downward scale 782 has a two-dimensionaldiffraction grating on its lower surface so that the measurement rangein the X-axis direction of each substrate holder 722 becomes wider(longer) than the measurement range in the Y-axis direction. Therelative positional relation between each upward head 80 x and 80 y anddownward scale 782 fixed to measurement table 624 is known.

Also, to each substrate holder 722, a head base 784 is fixed. On theupper surface of each head base 784, two upward X heads 80 x and twoupward Y heads 80 y (each refer to FIG. 29) are attached facing thecorresponding downward scale 782 (refer to FIG. 31). As for positionmeasurement operation of substrate P at the time of position control ofsubstrate P in the seventh embodiment, since the operation is roughlythe same as that of the sixth embodiment, the description thereaboutwill be omitted.

Eighth Embodiment

Next, a liquid crystal exposure apparatus according to an eighthembodiment will be described, using FIGS. 32 to 35. Since the structureof the liquid crystal exposure apparatus according to the eighthembodiment is roughly the same as that of the sixth embodiment describedabove, except for the point that the structure of a substrate stagedevice 820 and its measurement system is different, only the differentpoints will be described below, and for elements having the samestructure or function as the sixth embodiment described above will havethe same reference code as the sixth embodiment and the descriptionthereabout will be omitted.

Substrate stage device 820 of the eighth embodiment is equipped with afirst movable body (here, a substrate holder 822), a second movable body(here, X coarse movement stage 628), and a substrate measurement system880 and the like.

In the eighth embodiment, substrate holder 822 that holds substrate P isformed in a rectangular frame shape that surrounds the entire outerperiphery of substrate P, similarly to that of the sixth embodimentdescribed above (refer to FIG. 26 and the like). As for the drive systemto drive substrate holder 822 and substrate table 626, since the drivesystem is the same as that of the sixth embodiment described above, thedescription thereabout will be omitted. Note that substrate stage device820 of the eighth embodiment also has air guide 734 that supportssubstrate holder 822 from below in a non-contact manner, similarly tothe seventh embodiment described above (refer to FIG. 30).

Next, substrate measurement system 880 will be described. In the sixthembodiment described above (refer to FIGS. 23, 26 and the like), whileposition information on substrate holder 622 was obtained viameasurement table 624 with optical surface plate 18 a serving as areference, in the eighth embodiment, position information on substrateholder 822 is obtained via X coarse movement stage 628 for movingsubstrate table 626 in the X-axis direction with optical surface plate18 a serving as a reference. As for this point, substrate measurementsystem 880 is conceptually common with substrate measurement system 250(refer to FIG. 8 and the like) according to the second embodimentdescribed above. Note that while X coarse movement stage 628 in theeighth embodiment consists of a pair of plate shaped (strip shaped)members (refer to FIG. 34) extending in the X-axis direction that isarranged corresponding to the pair of base frames 634, since thefunction is the same, the stage will be described having the samereference code as X coarse movement stage 628 of the sixth embodimentfor convenience.

As is shown in FIG. 34, to each of the upper surface the pair of Ystators 638 fixed to X coarse movement stage 628, an upward scale 882 isfixed, similarly to the second embodiment described above (refer to FIG.9). Since the structure and function of upward scale 882 are the same asthose of upward scale 252 (refer to FIG. 9) of the second embodimentdescribed above, the description thereabout will be omitted here.

As is shown in FIG. 33, to each of the end near the +X side and the endnear the −X side of substrate holder 822, a pair of head bases 884 isfixed arranged apart in the Y-axis direction. To each of the total offour head bases 884, one each of downward X head 74 x, downward Y head74 y, and a downward Z head 74 z are attached (refer to FIG. 33) to faceupward scale 882 (refer to FIG. 34). Since the structure and function ofX head 74 x and Y head 74 y are the same as those of X head 74 x and Yhead 74 y (each refer to FIG. 3 and the like) of the first embodimentdescribed above, the description thereabout will be omitted here. In theeighth embodiment, the total of four downward X heads 74 x and thecorresponding upward scales 882 structure four X linear encoder systems(refer to FIG. 35), and the total of four downward Y heads 74 y and thecorresponding upward scales 882 also structure four Y linear encodersystems (refer to FIG. 35). The main controller (not shown) obtainsposition information (first information) on substrate holder 822 in theX-axis direction, the Y-axis direction, and the θz direction with Xcoarse movement stage 628 serving as a reference, appropriately usingthe output of the four X linear encoder systems and the four Y linearencoder systems.

While the structure of downward Z head 74 z is not limited inparticular, it is possible to use a known laser displacement sensor. Zhead 74 z uses a grating surface (reflection surface) of the opposingupward scale 882 (refer to FIG. 35), so as to measures displacementamount in the Z-axis direction of head base 884. The main controller(not shown) obtains displacement amount information on substrate holder822 (that is, substrate P) in the Z tilt direction with respect to Xcoarse movement stage 628, based on the output of the total of four Zheads 74 z.

Referring back to FIG. 34, to each of the end near the +Y side and theend near the −Y side of Y stators 638, a pair of head bases 886 is fixedarranged apart in the X-axis direction. To each of the total of eighthead bases 886, one each of upward X head 80 x, upward Y head 80 y, andan upward Z head 80 z is attached. Since the structure and function of Xhead 80 x and Y head 80 y are the same as those of X head 80 x and Yhead 80 y (each refer to FIG. 3 and the like) of the first embodimentdescribed above, the description thereabout will be omitted here.Information (third information) on relative positional relation betweeneach of the heads 80 x, 80 y, and 80 z and upward scales 882 describedabove is known.

To the lower surface of optical surface plate 18 a (refer to FIG. 32),one downward scale 888 is fixed, corresponding to the pair of head bases884 described above. That is, as is shown in FIG. 35, to the lowersurface of optical surface plate 18 a, a total of four downward scales888 are fixed. Since the structure and function of downward scale 888are the same as those of downward scale 254 (refer to FIG. 8) of thesecond embodiment described above, the description thereabout will beomitted here. In the eighth embodiment, the total of eight upward Xheads 80 x and the corresponding downward scales 888 structure eight Xlinear encoder systems (refer to FIG. 35), and the total of eight upwardY heads 80 y and the corresponding downward scales 888 also structureeight Y linear encoder systems (refer to FIG. 35). The main controller(not shown) obtains position information (second information) on Xcoarse movement stage 628 in the X-axis direction, the Y-axis direction,and the θz direction with optical surface plate 18 a serving as areference, appropriately using the output of the eight X linear encodersystems and the eight Y linear encoder systems.

As upward Z head 80 z, a displacement sensor similar to downward Z head74 z described above is used. The main controller (not shown) obtainsdisplacement amount information on X coarse movement stage 628 in the Ztilt direction with respect to optical surface plate 18 a, based on theoutput of the total of eight Z heads 74 z.

In the eighth embodiment, in addition to position information onsubstrate P (substrate holder 822) being obtained via X coarse movementstage 628 with optical surface plate 18 a serving as a reference (basedon the first to third information described above), position informationon substrate P (substrate holder 822) in the Z-tilt direction is alsoobtained via X coarse movement stage 628 with optical surface plate 18 aserving as a reference.

Ninth Embodiment

Next, a liquid crystal exposure apparatus according to a ninthembodiment will be described, using FIGS. 36 to 38. Since the structureof the liquid crystal exposure apparatus according to the ninthembodiment is roughly the same as that of the eighth embodimentdescribed above, except for the point that the structure of a substratestage device 920 (refer to FIG. 38) and its measurement system isdifferent, only the different points will be described below, and forelements having the same structure or function as the eighth embodimentdescribed above will have the same reference code as the eighthembodiment and the description thereabout will be omitted.

As is shown in FIG. 38, substrate stage device 920 according to theninth embodiment is equipped with a pair of substrate holders 922 whichis arranged physically separated, similarly to the seventh embodiment(refer to FIG. 29) described above. The point that one of the substrateholders 922 holds the end near the +X side of substrate P, and the othersubstrate holder 922 holds the end near the −X side of substrate P, andthe point that the pair of substrate holders 922 is moved independentlywith respect to X coarse movement stage 628 by 3-DOF motors are alsosimilar to those of the seventh embodiment described above.

The structure and operation of a substrate measurement system 980 (referto FIG. 38) according to the ninth embodiment is the same as those ofthe eighth embodiment, except for the point that position information oneach of the pair of substrate holders 922 can be obtained independently.That is, as is shown in FIG. 36, to each substrate holder 922, a pair ofhead bases 884 is fixed arranged apart in the Y-axis direction. To headbases 884, downward heads 74 x, 74 y, and 74 z are attached to face(refer to FIG. 38) upward scales 882 (each refer to FIG. 37) fixed onthe upper surface of Y stators 638. Since the structure and theoperation of the position measurement system of X coarse movement stage628, with optical surface plate 18 a serving as a reference, are thesame as those of the seventh embodiment described above, the descriptionthereabout will be omitted.

Tenth Embodiment

Next, a liquid crystal exposure apparatus according to a tenthembodiment will be described, using FIGS. 39 to 43. Since the structureof the liquid crystal exposure apparatus according to the tenthembodiment is roughly the same as that of the ninth embodiment describedabove, except for the point that the structure of a substrate stagedevice 1020 (refer to FIG. 41 and the like) and its measurement systemare different, only the different points will be described below, andfor elements having the same structure or function as the ninthembodiment described above will have the same reference code as theninth embodiment and the description thereabout will be omitted.

In the ninth embodiment (refer to FIG. 38) described above, whilesubstrate P was held by substrate holders 922 near both ends in theX-axis direction, as is shown in FIG. 39, in the tenth embodiment, thepoint different is that substrate P is held by suction only near an endon one side in the X-axis direction (in the embodiment, the −X side) bysubstrate holder 922. As for substrate holder 922, since the holder isthe same as that of the ninth embodiment described above, thedescription thereabout will be omitted here. Also, as for the structureand operation of a substrate measurement system 1080 (refer to FIG. 41)according to the tenth embodiment, since they are also the same as thoseof the ninth embodiment, the description thereabout will be omittedhere.

In the tenth embodiment, since there is no member (a membercorresponding to substrate holder 922 on the +X side in the ninthembodiment described above) to hold the end near the +X side ofsubstrate P, as is shown in FIG. 40, Y stator 638 is arranged only onthe −X side of substrate table 626. Therefore, in substrate stage device1020, a base frame 1024 is shorter than that of substrate stage device920 (refer to FIG. 38) according to the ninth embodiment described aboveand is compact as a whole. Note that connecting members 1022 whichconnects Y stator 638 to air guide 734 in the embodiment has rigidityalso in the X-axis direction, which allows Y stator 638 to push or pull(push/pull) substrate table 626. Also, since there is no member to holdthe end near the +X side of substrate P, an exchange operation ofsubstrate P can be performed easily. Note that while X guide 648 thatsupports weight canceling device 42 is fixed on lower mount section 18 cas is shown in FIGS. 42 and 43, the structure is not limited to this,and the X guide 648 may be installed on floor F in a state physicallyseparated from apparatus main section 18.

Eleventh Embodiment

Next, a liquid crystal exposure apparatus according to an eleventhembodiment will be described, using FIGS. 44 to 47. Since the structureof the liquid crystal exposure apparatus according to the eleventhembodiment is roughly the same as that of the tenth embodiment describedabove, except for the point that the structure of a substrate stagedevice 1120 and its measurement system is different, only the differentpoints will be described below, and for elements having the samestructure or function as the tenth embodiment described above will havethe same reference code as the tenth embodiment and the descriptionthereabout will be omitted.

In substrate stage device 1120 according to the eleventh embodiment,substrate P is held by a substrate holder 1122 (refer to FIG. 47) onlynear an end on one side in the X-axis direction (in the embodiment, the−X side), as in the tenth embodiment described above (refer to FIG. 41and the like).

Substrate holder 1122, as is shown in FIG. 45, has a size in the widthdirection (X-axis direction) which is set slightly longer than that ofsubstrate holder 922 (refer to FIG. 39) according to the tenthembodiment described. Substrate holder 1122, as is shown in FIG. 44, issupported from below in a non-contact manner by an air guide 1124. Whilethe structure and function of air guide 1124 are roughly the same asthose of air guide 734 (refer to FIG. 30 and the like) of each of theseventh to tenth embodiment described above, the air guide is differenton the point that the size in the X-axis direction is set slightlylonger, corresponding to substrate holder 1122.

Next, a substrate measurement system 1180 will be described. Substratemeasurement system 1180, as is shown in FIG. 44, is similar to that ofthe tenth embodiment (refer to FIG. 41) described above on the pointthat position information on substrate holder 1122 is obtained via Xcoarse movement stage 628 with optical surface plate 18 a serving as areference, however, the arrangement of upward scale 882 and downwardheads 74 x and 74 y (refer to FIG. 45) is different.

Upward scale 882, as is shown in FIG. 44, is fixed to air guide 1124that supports substrate holder 1122 by levitation. The height positionof the upper surface (guide surface) of air guide 1124 and the heightposition of the grating surface (surface subject to measurement) ofupward scale 882 is set about the same. Air guide 1124 is fixed to stagemain section 632, therefore, upward scale 882 moves so that its positionin the XY plane with respect to substrate P stays within a predeterminedrange. In substrate holder 1122, a recess section is formed that opensdownward, and in the recess section, one pair each of downward heads 74x, 74 y, and 74 z (each refer to FIG. 45) are attached facing upwardscale 882. As for the position measurement operation of substrate holder1122, since the operation is the same as that of the tenth embodimentdescribed above, the description thereabout will be omitted.

Also, in the tenth embodiment described above, while head bases 886(each refer to FIG. 41 and the like) were fixed to Y stator 638, in theeleventh embodiment, as is shown in FIG. 46, head bases 886 are fixed toair guide 1124. One pair each of head bases 886 are fixed to both endsnear the edge in the longitudinal direction of air guide 1124. As forposition measurement operation of X coarse movement stage 628 that usesdownward scale 888 fixed to optical surface plate 18 a (refer to FIG.44), since the operation is the same as that of the tenth embodimentdescribed above, the description thereabout will be omitted.

In the eleventh embodiment, position information on substrate holder1122 is obtained via air guide 1124 with optical surface plate 18 aserving as a reference. Since air guide 1124 is fixed to stage mainsection 632, it is hardly affected by disturbance, which can improveexposure accuracy. Also, compared to the tenth embodiment and the likedescribed above, since the position of upward scale 882 and downwardscale 888 becomes closer to the center position of projection opticalsystem 16, errors become smaller, which can improve exposure accuracy.

Twelfth Embodiment

Next, a liquid crystal exposure apparatus according to a twelfthembodiment will be described, using FIGS. 48 to 54. Since the structureof the liquid crystal exposure apparatus according to the twelfthembodiment is roughly the same as that of the seventh embodimentdescribed above, except for the point that the structure of a substratestage device 1220 and its measurement system is different, only thedifferent points will be described below, and for elements having thesame structure or function as the seventh embodiment described abovewill have the same reference code as the seventh embodiment and thedescription thereabout will be omitted.

As is shown in FIG. 31 and the like, in the seventh embodiment describedabove, while substrate P was held near both ends in the X-axis directionby the pair of substrate holders 722 which moves in long strokes in theY-axis direction, in the twelfth embodiment, as is shown in FIG. 53, thepoint differs in which substrate P is held near both ends in the Y-axisdirection by a pair of substrate holders 1222 which moves in longstrokes in the X-axis direction. In substrate stage device 1220, at thetime of scanning exposure operation, by only one pair of substrateholders 1222 being moved in the X-axis direction with respect toprojection optical system 16 (refer to FIG. 48), scanning exposureoperation on substrate P is performed. Also, at the time of movementbetween exposure areas, the pair of substrate holders 1222 movesintegrally with a system including substrate table 626 in the Y-axisdirection. That is, substrate stage device 1220 has a structure ofsubstrate stage device 720 (refer to FIG. 31 and the like) according tothe seventh embodiment described above being rotated around the Z-axisby 90 degrees with respect to projection optical system 16. Next, thestructure of substrate stage device 1220 will be described.

As is shown in FIG. 50, on lower mount section 18 c, three surfaceplates 1224 extending in the Y-axis direction are arranged, set apart inthe X-axis direction at a predetermined spacing. On surface plate 1224in the center, weight canceling device 42 is mounted via linear guidedevice 1226. Also, on surface plates 1224 on the +X side and −X side, Zactuators 1228 are mounted via linear guide devices 1226. The point thatweight canceling device 42 supports substrate table 626 (each refer toFIG. 48) from below via stage main section 632 is the same as the sixthembodiment (refer to FIG. 23 and the like) and the like described above.

As is shown in FIG. 51, a Y coarse movement stage 1230 is mounted on apair of base frames 1232 extending in the Y-axis direction, and is movedin long strokes in the Y-axis direction by Y linear actuators (notshown). Weight canceling device 42 and the two Z actuators 1228described above (each refer to FIG. 50) are each connected to Y coarsemovement stage 1230 by connecting members 46 (refer to FIG. 48), andmove in the Y-axis direction integrally with Y coarse movement stage1230. Stage main section 632 is also connected to Y coarse movementstage 1230 by connecting members 46 (refer to FIG. 48), and moves in theY-axis direction integrally with Y coarse movement stage 1230. At bothends near the edge in the Y-axis direction of Y coarse movement stage1230, stators 1234 are attached extending in the X-axis direction.

As is shown in FIG. 52, on the +Y side and the −Y side of substratetable 626, air guides 1236 are arranged each corresponding to the pairof substrate holders 1222 (refer to FIG. 53). Air guides 1236 are fixedto stage main section 632 via support members 1238 (refer to FIG. 48).The Z position of the upper surface of air guides 1236 is set to aposition lower than the Z position of the upper surface of substratetable 626.

On the +X side and the −X side of substrate table 626, a plurality of(four each, in the embodiment) air guides 1240 is arranged to supportsubstrate P from below. The Z position of the upper surface of airguides 1240 is set roughly the same as the Z position of the uppersurface of substrate table 626. Air guides 1240, when substrate P movesrelatively in the X-axis direction with respect to substrate table 626such as at the time of scanning exposure and the like, work togetherwith substrate table 626 and supports substrate P from below (refer toFIG. 54).

On each of the +Y side and the −Y side of the four air guides 1240, airguides 1242 are arranged corresponding to the pair of substrate holders1222. Air guides 1242 are members similar to air guides 1236 describedabove, and the Z position of the upper surface is set roughly the sameas air guides 1236. Air guides 1242, together with air guides 1236,support substrate holders 1222 from below (refer to FIG. 54) whensubstrate holders 1222 move relatively in the X-axis direction withrespect to substrate table 626. Air guides 1240 and 1242 are mounted onZ actuators 1228 (refer to FIG. 50) described above, via a common basemember. Since Z actuators 1228 and weight canceling device 42 (refer toFIG. 50) move integrally in the Y-axis direction, air guides 1240, 1242,1236, and substrate table 626 move integrally in the Y-axis direction.

As is shown in FIG. 49, the pair of substrate holders 1222 are arrangedsandwiching the center (center of gravity position) of substrate P, andholds the lower surface of substrate P by suction, using suction pads1244. Also, to each substrate holder 1222, a mover 1246 is attachedwhich structures a 2-DOF motor together with stator 1234 (refer to FIG.51) described above. The main controller (not shown) moves eachsubstrate holder 1222 with long strokes in the X-axis direction withrespect to substrate table 626 (refer to FIG. 52) via the corresponding2-DOF motor, and also gives thrust in the Y-axis direction to substrateholders 1222 so that positional relation in the Y-axis direction withsubstrate table 626, Y coarse movement stage 1230 (refer to FIG. 51) andthe like stays within a predetermined range.

As is described above, in substrate stage device 1220, as is shown inFIG. 54, by the pair of substrate holders 1222 being moved in the X-axisdirection by 2-DOF motors on air guides 1236 and 1242 at the time ofscanning exposure operation and the like, scanning exposure operation isperformed on substrate P. Also, at the time of movement between exposureareas, the pair of substrate holders 1222 and a system includingsubstrate table 626 (substrate table 626, Y coarse movement stage 1230,stators 1234, air guides 1236, 1240, 1242 and the like) move integrallyin the Y-axis direction.

Next, a substrate measurement system 1280 (refer to FIG. 53) accordingto the twelfth embodiment will be described. Substrate measurementsystem 1280 conceptually resembles substrate measurement system 70(refer to FIG. 4) according to the first embodiment. That is, downwardheads 74 x and 74 y are attached in pairs (each refer to FIG. 49) viahead bases 1282 to a member (each of the pair of substrate holders 1222)holding substrate P, and downward heads 74 x and 74 y face thecorresponding upward scale 1284 attached to the upper surface of stators1234. The main controller (not shown) obtains position information(first information) on each substrate holder 1222 in the X-axisdirection, the Y-axis direction, and the θz direction independently,appropriately using the output of two X linear encoder systems and two Ylinear encoder systems.

Also, as is shown in FIG. 51, in the center in the longitudinaldirection of stator 1234, head base 1286 is fixed. To head base 1286,upward heads 80 x and 80 y are attached in pairs, and upward heads 80 xand 80 y structure X linear encoder systems and Y linear encoder systemswith the corresponding downward scale 1288 fixed to the lower surface ofoptical surface plate 18 a (refer to FIG. 48). Positional relation(third information) between upward scale 1284 and each upward head 80 xand 80 y is known. The main controller (not shown) obtains positioninformation (second information) on Y coarse movement stage 1230 withina horizontal plane, appropriately using the output of four X linearencoder systems and four Y linear encoder systems.

Thirteenth Embodiment

Next, a liquid crystal exposure apparatus according to a thirteenthembodiment will be described, using FIGS. 55 to 58. Since the structureof the liquid crystal exposure apparatus according to the thirteenthembodiment is roughly the same as that of the twelfth embodimentdescribed above, except for the point that the structure of a substratestage device 1320 and its measurement system is different, only thedifferent points will be described below, and for elements having thesame structure or function as the twelfth embodiment described abovewill have the same reference code as the twelfth embodiment and thedescription thereabout will be omitted.

Similar to substrate stage device 1220 (refer to FIG. 53 and the like)according to the twelfth embodiment, in substrate stage device 1320,substrate P, as is shown in FIG. 58, is held near both ends in theY-axis direction by a pair of substrate holders 1322. The point that thepair of substrate holders 1322 is moved in long strokes in the X-axisdirection by 2-DOF motors and is finely moved in the Y-axis directionand the θz direction is similar to the twelfth embodiment describedabove. Here, in the twelfth embodiment described above, while substrateholders 1222 (refer to FIG. 53 and the like) were supported from belowby either air guides 1236 or the pair of air guides 1242 depending onthe position in the X-axis direction, substrate holders 1322 in thethirteenth embodiment is supported from below, by a single air guide1324 set to a length that can cover the whole range of the movable areain the X-axis direction. Air guide 1324, as is shown in FIG. 55, isconnected to stage main section 632, and is movable in the Y-axisdirection integrally with substrate table 626.

Next, a structure and operation of a substrate measurement system 1380according to the thirteenth embodiment will be described. Substratemeasurement system 1380 conceptually has a structure of substratemeasurement system 1180 (refer to FIG. 44 and the like) according to theeleventh embodiment described above being rotated at an angle of 90degrees around the Z-axis. That is, in the thirteenth embodiment, to theupper surface of air guide 1324, an upward scale 1382 is fixed, as isshown in FIG. 57. In the eleventh embodiment described above, whileupward scale 882 (refer to FIG. 46 and the like) was arranged so thatthe measurement range of position information in the Y-axis directionwas wider than that of the X-axis direction (the Y-axis direction was tobe the longitudinal direction), with upward scale 1382 in theembodiment, the scale is arranged so that the measurement range ofposition information in the X-axis direction is wider than that of theY-axis direction (the X-axis direction is to be the longitudinaldirection).

Substrate holders 1322, as is shown in FIG. 55, has a recess sectionformed that opens downward, similarly to substrate holder 1122 (refer toFIG. 44 and the like) according to the eleventh embodiment describedabove, and in the recess section, downward heads 74 x, 74 y, and 74 z(each refer to FIG. 56) are formed in pairs, attached to face upwardscale 1382 (refer to FIG. 58).

As is shown in FIG. 57, at both ends near the edge in the longitudinaldirection of air guide 1324, head bases 1384 are fixed, and to each headbase 1384, two each of upward heads 80 x, 80 y, and 80 z are attachedfacing the corresponding downward scale 1386 fixed to the lower surfaceof optical surface plate 18 a (refer to FIG. 55). With substratemeasurement system 1380 according to the thirteenth embodiment as well,similarly to substrate measurement system 1280 (refer to FIG. 53 and thelike) of the twelfth embodiment described above, position information onsubstrate P (the pair of substrate holders 1322) is obtained via Ycoarse movement stage 1230 with optical surface plate 18 a serving as areference.

Fourteenth Embodiment

Next, a liquid crystal exposure apparatus according to a fourteenthembodiment will be described, using FIG. 59. Since the structure of theliquid crystal exposure apparatus according to the fourteenth embodimentis roughly the same as that of the thirteenth embodiment describedabove, except for the point that the structure of a substrate stagedevice 1420 and its measurement system is different, only the differentpoints will be described below, and for elements having the samestructure or function as the thirteenth embodiment described above willhave the same reference code as the thirteenth embodiment and thedescription thereabout will be omitted.

In the thirteenth embodiment (refer to FIG. 58) described above, whilesubstrate P was held near both ends in the Y-axis direction by substrateholders 1322, as is shown in FIG. 59, in the fourteenth embodiment, thepoint in which substrate P is held by suction by a substrate holder 1422at only one side near the edge in the Y-axis direction (in theembodiment, the +Y side) is different. As for substrate holder 1422,since the holder is the same as that of the twelfth embodiment describedabove except for the point that the holder is moved by a 3-DOF motorwith respect to a stator 1424, the description thereabout will beomitted. Connecting members 1426 that connect stator 1424 and air guide1324 also has rigidity in the Y-axis direction, which makes it possiblefor stator 1424 to push or pull (push/pull) substrate table 626. Also,as for the structure and operation of a substrate measurement system1480 according to the fourteenth embodiment, since they are also thesame as those of the thirteenth embodiment, the description thereaboutwill be omitted here.

Fifteenth Embodiment

Next, a liquid crystal exposure apparatus according to a fifteenthembodiment will be described, using FIGS. 60 to 63. Since the structureof the liquid crystal exposure apparatus according to the fifteenthembodiment is roughly the same as that of the first or the sixthembodiment described above, except for the point that the structure of asubstrate stage device 1520 and its measurement system is different,only the different points will be described below, and for elementshaving the same structure or function as the first or the sixthembodiment described above will have the same reference code as thefirst or the sixth embodiment and the description thereabout will beomitted.

As is shown in FIG. 60, substrate stage device 1520 is equipped with afirst movable body (here, a substrate holder 1522) and a second movablebody (here, Y coarse movement stage 24).

As is shown in FIG. 62, substrate holder 1522 is formed in a frame shape(picture frame shape) which is rectangular in a planar view, similarlyto substrate holder 622 in the sixth embodiment (refer to FIG. 26 andthe like) described above, and substrate P is arranged within an openingof substrate holder 1522. Substrate holder 1522 has four suction pads1524, and holds substrate P from below by suction near the center ateach of the four sides.

Of substrate P, the exposure area including the center is supported frombelow in a non-contact manner by substrate table 626, as is shown inFIG. 60. Substrate table 626, similarly to that of the sixth embodiment(refer to FIG. 26 and the like) described above, performs flatnesscorrection substrate P in a non-contact state. Also, although it is notshown in FIG. 60 and the like, to the lower surface of substrate table626, stage main section 632 (refer to FIG. 23) is fixed, similarly tothat of the sixth embodiment described above. Stage main section 632(not shown), as is shown in FIG. 63, is connected to X coarse movementstage 26 via a plurality of connecting members 1526, in a state whererelative movement in the Z-tilt direction is allowed; accordingly,substrate table 626 moves in long strokes in the X-axis and the Y-axisdirections, integrally with X coarse movement stage 26. Since thestructure and operation of X coarse movement stage 26, Y coarse movementstage 24 and the like are the same as those of the first embodiment(refer to FIG. 4 and the like) described above, the descriptionthereabout will be omitted.

Also, as is shown in FIG. 63, from stage main section 632 (not shown inFIG. 63, refer to FIG. 23), table members 1528 are protruding outward ina total of four directions; in the ±Y directions and the ±X directions.As is shown in FIG. 60, substrate holder 1522 is mounted on the fourtable members 1528 via an air bearing (not shown) in a non-contactstate. Also, substrate holder 1522 is moved in fine strokes in theX-axis, the Y-axis, and the θz directions with respect to substratetable 626 by a plurality of linear motors structured by a plurality ofmovers 1530 (refer to FIG. 62) attached to substrate holder 1522 and aplurality of stators 1532 (refer to FIG. 63) attached to stage mainsection 632.

While substrate holder 622 of the sixth embodiment described above wasrelatively movable (refer to FIG. 27) in long strokes in the Y-axisdirection separate from substrate table 626, in the fifteenthembodiment, the main controller (not shown) gives thrust to substrateholder 1522 using the plurality of linear motors described above, sothat the position between substrate holder 1522 and substrate table 626stays within a predetermined range, as is shown in FIG. 61. Accordingly,the entire exposure area of substrate P is supported from below at alltimes by substrate table 626.

Next, a substrate measurement system 1580 according to the fifteenthembodiment will be described. Substrate measurement system 1580 isconceptually roughly the same as substrate measurement system 70according to the first embodiment described above, and positioninformation on substrate holder 1522 within the horizontal plane isobtained via Y coarse movement stage 24, with optical surface plate 18 a(refer to FIG. 1 and the like) serving as a reference.

That is, to substrate holder 1522, as is shown in FIG. 62, a pair ofhead bases 88 is fixed, and to each head base 88, two each of downward Xheads 74 x and downward Y heads 74 y are attached (refer to FIG. 62).Also, as is shown in FIG. 63, to Y coarse movement stage 24, a pair ofscale bases 84 is attached via arm member 86, and on the upper surfaceof each scale base 84, upward scale 72 extending in the X-axis direction(measurable range in the X-axis direction is longer than measurablerange in the Y-axis direction) is fixed. Position information onsubstrate holder 1522 with respect to Y coarse movement stage 24 isobtained by an encoder system structured by each of the heads 74 x and74 y described above and the corresponding scale 72.

Also, to each of the pair of scale bases 84 attached to Y coarsemovement stage 24, head base 96 is fixed, and to each head base 96, twoeach of upward X heads 80 x and upward Y heads 80 y are attached (referto FIG. 63). To the lower surface of optical surface plate 18 a (referto FIG. 1 and the like), downward scale 78 (refer to FIG. 60) is fixed,corresponding to each head base 96 and extending in the Y-axis direction(measurable range in the Y-axis direction is longer than measurablerange in the X-axis direction). Position information on Y coarsemovement stage 24 with respect to optical surface plate 18 a is obtainedby an encoder system structured by each of the heads 80 x and 80 ydescribed above and the corresponding scale 78.

Sixteenth Embodiment

Next, a liquid crystal exposure apparatus according to a sixteenthembodiment will be described, using FIG. 64. Since the structure of theliquid crystal exposure apparatus according to the sixteenth embodimentis roughly the same as that of the sixth or the fifteenth embodimentdescribed above, except for the point that the structure of a substratestage device 1620 and its measurement system is different, only thedifferent points will be described below, and for elements having thesame structure or function as the sixth or the fifteenth embodimentdescribed above will have the same reference code as the sixth or thefifteenth embodiment and the description thereabout will be omitted.

The structure (including the drive system) of substrate holder 1522,substrate table 626 and the like that substrate stage device 1620according to the sixteenth embodiment has is roughly the same as thefifteenth embodiment (refer to FIG. 60 and the like) described above.While substrate measurement system 1580 (refer to FIG. 60 and the like)of the fifteenth embodiment described above obtained positioninformation on substrate holder 1522 via Y coarse movement stage 24 withoptical surface plate 18 a serving as a reference (that is, thestructure was similar to that of substrate measurement system 70 of thefirst embodiment), a substrate measurement system 1680 according to thesixteenth embodiment is different on the point that position informationon substrate holder 1522 is obtained via measurement table 624 withoptical surface plate 18 a serving as a reference, similarly to that ofthe sixth embodiment described above.

That is, to substrate holder 1522 according to the sixteenth embodiment,a pair of head bases 688 is fixed similarly to that of the sixthembodiment (refer to FIG. 24) described above, and to each head base688, two each of upward X heads 80 x and upward Y heads 80 y areattached. Also, to the lower surface of optical surface plate 18 a,measurement table 624 is attached that can be moved so that the positionin the Y-axis direction with respect to substrate holder 1522 stayswithin a predetermined range, corresponding to the pair of head bases688. Position information on substrate holder 1522 is obtained by alinear encoder system structured by each of the heads 80 x and 80 y anddownward scale 686 extending in the X-axis direction fixed to the lowersurface of the corresponding measurement table 624. Also, positioninformation on measurement table 624 is obtained by a linear encodersystem, structured by upward X heads 80 x and upward Y heads 80 yattached to measurement table 624 and downward scale 684 extending inthe Y-axis direction fixed to the lower surface of optical surface plate18 a.

Seventeenth Embodiment

Next, a liquid crystal exposure apparatus according to a seventeenthembodiment will be described, using FIG. 65. Since the structure of theliquid crystal exposure apparatus according to the seventeenthembodiment is roughly the same as that of the fifteenth or the sixteenthembodiment described above, except for the point that the structure of asubstrate stage device 1720 and its measurement system is different,only the different points will be described below, and for elementshaving the same structure or function as the fifteenth or the sixteenthembodiment described above will have the same reference code as thefifteenth or the sixteenth embodiment and the description thereaboutwill be omitted.

The structure (including the drive system) of substrate holder 1522,substrate table 626 and the like that substrate stage device 1720according to the seventeenth embodiment has is roughly the same as thefifteenth embodiment (refer to FIG. 60 and the like) described above.While substrate measurement system 1580 (refer to FIG. 60 and the like)of the fifteenth embodiment described above obtained positioninformation on substrate holder 1522 via Y coarse movement stage 24 withoptical surface plate 18 a serving as a reference (that is, thestructure was similar to that of substrate measurement system 70 of thefirst embodiment), a substrate measurement system 1780 according to theseventeenth embodiment is different on the point that positioninformation on substrate holder 1522 is obtained via Y coarse movementstage 24 and a measurement table 1782 with optical surface plate 18 aserving as a reference.

In substrate stage device 1720 according to the seventeenth embodiment,to Y coarse movement stage 24, a scale base 1784 is fixed via arm member86, similarly to that of the fifteenth embodiment (refer to FIG. 63 andthe like) described above. Note that although it is not shown in FIG.65, scale base 1784 is arranged one each on the +Y side and on the −Yside of substrate holder 1522, similarly to that of the fifteenthembodiment described above. While measurement table 1782 is also notshown, the measurement table is similarly arranged one each on the +Yside and on the −Y side of projection optical system 16, correspondingto scale base 1784.

To the upper surface of scale base 1784, an upward scale 1786 used formeasuring the position of substrate holder 1522 and an upward scale 1788used for measuring the position of measurement table 1782 are attachedat a predetermined spacing in the Y-axis direction. Upward scales 1786and 1788 have two-dimensional diffraction gratings on their uppersurface, formed so that the measurement range of position information inthe X-axis direction becomes wider than that of the Y-axis direction(the X-axis direction is to be the longitudinal direction). Positionalrelation (third information) between upward scale 1786 and upward scale1788 is to be known. Note that the pitch of the two-dimensionaldiffraction gratings formed on upward scales 1786 and 1788 may be thesame, or may be different. Also, instead of the two upward scales 1786and 1788, scale base 1784 may have one wide upward scale that can beused for measuring the position of both substrate holder 1522 andmeasurement table 1782.

To substrate holder 1522, similarly to that of the fifteenth embodiment(refer to FIG. 63 and the like) described above, two each of downwardheads 74 x and 74 y are attached, via head base 88. Since the point thatposition information on substrate holder 1522 within the XY plane withrespect to Y coarse movement stage 24 is obtained by an encoder systemstructured by downward heads 74 x and 74 y and the corresponding upwardscale 1786 is similar to that of the fifteenth embodiment (that is, thefirst embodiment) described above, the description thereabout will beomitted.

Measurement table 1782 is moved in predetermined strokes in the Y-axisdirection by Y linear actuator 682, similarly to measurement table 624in the sixteenth embodiment (refer to FIG. 64) described above.Similarly to the sixteenth embodiment described above, to measurementtable 1782, two each of upward heads 80 x and 80 y are attached. Sincethe point that position information on measurement table 1782 within theXY plane with respect to optical surface plate 18 a is obtained by anencoder system structured by upward heads 80 x and 80 y and acorresponding downward scale 984 is similar to that of the sixteenthembodiment (that is, the sixth embodiment) described above, thedescription thereabout will be omitted.

Position information on Y coarse movement stage 24 within the XY planeis obtained via measurement table 1782 with optical surface plate 18 aserving as a reference. The measurement system for obtaining theposition information on Y coarse movement stage 24 is conceptually sameas the measurement system (encoder system) for obtaining positioninformation on substrate holder 1522 with respect to Y coarse movementstage 24. That is, two each of downward X heads 74 x and downward Yheads 74 y are attached to measurement table 1782, and positioninformation on Y coarse movement stage 24 within the XY plane withrespect to measurement table 1782 is obtained by an encoder systemstructured by the downward heads 74 x and 74 y and upward scale 1788.The main controller obtains position information on substrate holder1522 with optical surface plate 18 a serving as a reference, based onposition information on measurement table 1782 with respect to opticalsurface plate 18 a, position information on Y coarse movement stage 24with respect to measurement table 1782, and position information onsubstrate holder 1522 with respect to Y coarse movement stage 24described above.

Eighteenth Embodiment

Next, a liquid crystal exposure apparatus according to an eighteenthembodiment will be described, using FIGS. 66 to 68. Since the structureof the liquid crystal exposure apparatus according to the eighteenthembodiment is roughly the same as that of the first embodiment describedabove, except for the point that the structure of a substrate stagedevice 1820 and its measurement system is different, only the differentpoints will be described below, and for elements having the samestructure or function as the first embodiment described above will havethe same reference code as the first embodiment and the descriptionthereabout will be omitted.

In the first embodiment (refer to FIG. 2 and the like), while upwardscale 72 for obtaining position information on fine movement stage 22,and upward heads 80 x and 80 y for obtaining position information onupward scale 72 were each fixed to Y coarse movement stage 24, theeighteenth embodiment is different on the point that upward scale 72 andupward heads 80 x and 80 y are fixed to Y step guide 44 that weightcanceling device 28 is equipped with, as is shown in FIG. 67.

Upward scale 72 is fixed to the upper surface of scale base 84. Scalebase 84, as is shown in FIG. 66, is arranged one each on the +Y side andthe −Y side of fine movement stage 22. Scale base 84, as is shown inFIG. 67, is fixed to Y step guide 44 via an arm member 1886 formed in anL-shape when viewed from the X-axis direction. Accordingly, scale base84 (and upward scale 72) is movable in predetermined long strokes in theY-axis direction integrally with Y step guide 44 and Y coarse movementstage 24. As is described above, because Y step guide 44 is arranged inbetween the pair of X beams 36 that Y coarse movement stage 24 has (theZ position of X beams 36 partly overlaps the Z position of Y step guide44), through holes 45 are formed in X beams 36 that allow arm member1886 to penetrate (to prevent arm member 86 from coming into contactwith X beams 36).

The structure and operation of fine movement stage measurement system 76(refer to FIG. 6) including downward heads 74 x and 74 y, and upwardscale 72 are the same as those of the first embodiment described above,therefore, the description thereabout will be omitted Also, since thestructure and operation of coarse movement stage measurement system 82(refer to FIG. 6) including downward scale 78, and upward heads 80 x and80 y are also the same as those of the first embodiment described above,the description thereabout will be omitted However, in the embodiment,the point in which coarse movement stage measurement system 82 actuallymeasures position information on Y step guide 44 is different from thefirst embodiment described above. As is described so far, a substratemeasurement system 1870 of the embodiment obtains position informationon fine movement stage 22 (substrate P) via Y step guide 44 with opticalsurface plate 18 a serving as a reference.

According to the eighteenth embodiment, since upward scale 72 is fixedto Y step guide 44 which supports fine movement stage 22 (is included inthe same system as fine movement stage 22), influence of operation ofcoarse movement stages 24 and 26 can be suppressed compared to the firstembodiment described above, which can improve position measurementaccuracy of fine movement stage 22.

Nineteenth Embodiment

Next, a liquid crystal exposure apparatus according to a nineteenthembodiment will be described, using FIGS. 69 and 70. Since the structureof the liquid crystal exposure apparatus according to the nineteenthembodiment is roughly the same as that of the eighteenth embodimentdescribed above, except for the point that the structure of an apparatusmain section 1918 and a substrate measurement system 1970 is different,only the different points will be described below, and for elementshaving the same structure or function as the eighteenth embodimentdescribed above will have the same reference code as the eighteenthembodiment and the description thereabout will be omitted.

In the eighteenth embodiment (refer to FIG. 66) described above, whileapparatus main section 18 was installed on floor F via a vibrationisolation device 19 in a state where optical surface plate 18 a, middlemount section 18 b, and lower mount section 18 c were integrallyassembled, in the nineteenth embodiment, apparatus main section 1918, asis shown in FIG. 69, is different on the point that a part supportingprojection optical system 16 (hereinafter called a “first part”) and apart supporting Y step guide 44 (hereinafter called a “second part”) areinstalled on floor F in a state physically separated from each other.

Of apparatus main section 1918, the first part supporting projectionoptical system 16 is equipped with optical surface plate 18 a, a pair ofmiddle mount sections 18 b, and a pair of a first lower mount section 18d, and has a gate form (inverted U-shape) in a front view (when viewedfrom the X-axis direction). The first part is installed on floor F via aplurality of vibration isolation devices 19. Meanwhile, of apparatusmain section 1918, the second part supporting Y step guide 44 isequipped with a second lower mount section 18 e. The second lower mountsection 18 e consists of a plate shaped member, and is inserted inbetween the pair of the first lower mount sections 18 d. The secondlower mount section 18 e is installed on floor F via a plurality ofvibration isolation devices 19 different from the plurality of vibrationisolation devices 19 that support the first part described above. A gapis formed between the pair of first lower mount sections 18 d and thesecond lower mount section 18 e, and the first part and the second partare separated (isolated) in a vibrational manner. The point in which Ystep guide 44 is mounted on the second lower mount section 18 e viamechanical linear guide device 52 is the same as the eighteenthembodiment described above.

While it is partly omitted in FIG. 69, the structure of the pair of baseframes 30 is similar to that of the eighteenth (first) embodimentdescribed above. The pair of base frames 30 includes the second lowermount section 18 e, and is installed on floor F in a state vibrationallyisolated with an apparatus main section 218. The point in which Y coarsemovement stage 24 and X coarse movement stage 26 are mounted on the pairof base frames 30 and fine movement stage 22 is mounted on Y step guide44 via weight canceling device 28 are the same as the eighteenthembodiment described above.

Next, a structure and operation of a substrate measurement system 1970according to the nineteenth embodiment will be described. Note that thestructure and operation of a substrate stage device 1920 except for themeasurement system are the same as those of the eighteenth embodiment,the description thereabout will be omitted.

FIG. 70 shows a schematic view of substrate measurement system 1970according to the nineteenth embodiment. Of substrate measurement system1970, since the structure of fine movement stage measurement system 76(refer to FIG. 6) for obtaining position information on fine movementstage 22 (substrate holder 32 in actual) within the XY plane is the sameas that of the eighteenth (first) embodiment described above, thedescription thereabout will be omitted. With substrate measurementsystem 1970 according to the nineteenth embodiment, the structure of aZ-tilt position measurement system 1998 for obtaining positioninformation on substrate holder 32 in a direction intersecting with thehorizontal plane is different from that of the eighteenth (first)embodiment described above.

Z-tilt position measurement system 1998, as is shown in FIG. 70, obtainsposition information on substrate holder 32 in the Z-tilt direction viaY coarse movement stage 24 with optical surface plate 18 a (refer toFIG. 69) serving as a reference, similarly to fine movement stagemeasurement system 76.

As is shown in FIG. 69, to each of head bases 1988 fixed to the sidesurfaces on the +Y side and the −Y side of substrate holder 32, alongwith two downward X heads 74 x and two downward Y heads 74 y, twodownward Z head 74 z are attached arranged apart in the X-axis direction(refer to FIG. 70). As downward Z head 74 z, a known displacement sensoris used that irradiates a measurement beam on upward scale 72. The maincontroller (not shown) obtains displacement amount information on finemovement stage 22 in the Z tilt direction with respect to Y coarsemovement stage 24, based on the output of the total of four Z heads 74 z(refer to FIG. 9).

Also, to each of the pair of scale bases 84 fixed to the side surfaceson the +Y side and the −Y side of Y step guide 44, two head bases 1996are fixed, similarly to head bases 96 in the first embodiment describedabove (refer to FIG. 4). Also, as is shown in FIG. 70, to head bases1996, along with two upward X heads 84 x and two upward Y heads 80 y,one upward Z head 80 z is attached. While a laser displacement metersimilar to that of downward Z head 74 z is used for upward Z head 80 z,different kinds may be used in each of the Z head 74 z and 80 z. Themain controller (not shown) obtains displacement amount information on Ycoarse movement stage 24 in the Z tilt direction with respect to opticalsurface plate 18 a (refer to FIG. 69), based on the output of the totalof four upward Z heads 80 z (refer to FIG. 70).

In the nineteenth embodiment described so far, since positioninformation in the Z-tilt direction of substrate P can be obtained withoptical surface plate 18 a (that is, projection optical system 16)serving as a reference, position information in the Z-tilt direction ofsubstrate P can be acquired with high precision, along with positioninformation on substrate P within the XY plane. That is, as is disclosedin International Publication WO2015/147319 as an example, in the case ofobtaining position information on substrate P in the Z-tilt directionwith weight canceling device 42 serving as a reference, because weightcanceling device 42 is mounted on Y step guide 44, an error may occur inposition measurement of substrate P due to vibration and the like at thetime of movement of Y step guide 44. Meanwhile, in the embodiment, evenif vibration and the like occurs at the time of movement of Y step guide44, because position information on Y step guide 44 is measured at alltimes with optical surface plate 18 a serving as a reference, even ifposition information on substrate P is measured via Y step guide 44,position shift of Y step guide 44 is not reflected in the measurementresults of substrate P. Accordingly, position information on substrate Pcan be measured with high accuracy.

Also, of an apparatus main section 1980, since the second part (secondlower mount section 18 e) supporting Y step guide 44 is isolatedvibrationally from the first part supporting projection optical system16, when Y step guide 44 moves in the Y-axis direction with the movementof substrate P in the Y-axis direction, influence on projection opticalsystem 16 of vibration, deformation and the like caused by the movementcan be suppressed, which can improve the exposure accuracy.

Note that in the first embodiment described above, while the case hasbeen described in which the pair of head bases 88 each has four heads(one pair each of downward X heads 74 x and downward Y heads 74 y) formeasuring the position of fine movement stage 22 (substrate holder 32)and a total of eight heads for measuring the potion of the substrateholder was provided, the number of heads for measuring the position ofthe substrate holder may be less than eight. Hereinafter, such anembodiment will be described.

Twentieth Embodiment

Next, a twentieth embodiment will be described, based on FIGS. 71 to74C. Since the structure of the liquid crystal exposure apparatusaccording to the twentieth embodiment is the same as the firstembodiment previously described except for the structure of a part of asubstrate measurement system 2070, only the different points will bedescribed below, and for elements having the same structure and functionas the first embodiment will have the same reference code as the firstembodiment and the description thereabout will be omitted.

FIG. 71 shows substrate holder 32 and the pair of head bases 88 ofsubstrate measurement system 2070 according to the twentieth embodimentin a planar view, along with projection optical system 16. In FIG. 71,to make the description comprehensive, illustration of Y coarse movementstage 24 and the like is omitted. Also, in FIG. 71, head bases 88 areillustrated in a dotted line.

With the liquid crystal exposure apparatus according to the twentiethembodiment, as is shown in FIG. 71, in each of the areas on the +Y sideand the −Y side of substrate holder 32 with the substrate mounting areain between, scale bases 84 are arranged. On the upper surface of eachscale base 84, encoder scales 2072 (hereinafter simply referred to asscales 2072), such as for example, five scales, are arranged at apredetermined spacing in the X-axis direction so that the grating areasare arranged separately in the X-axis direction.

Each of the plurality of scales 2072 has a grating area (gratingsection) where a reflective two-dimensional grating is formed. Note thatwhile the grating may be formed to cover the entire area of scales 2072,since it is difficult to form the grating with good precision at theedge of scales 2072, in the embodiment, the grating is to be formed sothat the periphery of the grating area in scales 2072 becomes a marginpart. Therefore, spacing between the grating areas is larger than thespacing between the pair of scales 2072 adjacent in the X-axisdirection, and the period while an area other than the grating areas isirradiated with the measurement beam is to be a non-measurement period(also called a non-measurement section; however, hereinafter referred tocollectively as non-measurement period) in which position measurementcannot be performed.

With the five scales 2072 arranged on the +Y side of substrate holder 32and the five scales 2072 arranged on the −Y side, while the spacingbetween adjacent scales 2072 (grating area) is the same, the arrangementposition of the five scales 2072 on the −Y side is, as a whole arrangedshifted to the +X side by a predetermined distance D (a distanceslightly larger than the spacing between adjacent scales 2072 (gratingarea)) with respect to the five scales 2072 on the +Y side. This is toprevent a state from occurring in which two or more heads of the totalof four heads; two X heads 74 x and two Y heads 74 y to be describedlater on that measure position information on substrate holder 32, donot face any of the scales (that is, to avoid a non-measurement periodin which the measurement beam moves off from the scale from overlappingamong the four heads).

On the upper surface of each scale 2072, a reflective two-dimensionaldiffraction grating (two-dimensional grating) RG is formed, having apredetermined pitch (e.g. 1 μm) whose periodic direction is in theX-axis direction and the Y-axis direction. In the description below, thegrating area described earlier will also be simply calledtwo-dimensional grating RG. Note that in FIG. 71, for convenience ofillustration, the spacing (pitch) between the grid lines of thetwo-dimensional grating RG is illustrated much wider than the actualspacing. The same also applies to other drawings that will be describedbelow. In the description below, the five scales 2072 arranged in thearea on the +Y side of substrate holder 32 is to be referred to as afirst grating group, and the five scales 2072 arranged in the area onthe −Y side of substrate holder 32 is to be referred to as a secondgrating group

To the lower surface (surface on the −Z side) of one of head bases 88positioned on the +Y side, X head 74 x and Y head 74 y are fixed apartby a predetermined spacing (a distance larger than the spacing betweenadjacent scales 2072) in the X-axis direction, in a state each facingscales 2072. Similarly, to the lower surface (surface on the −Z side) ofthe other head base 88 positioned on the −Y side, Y head 74 y and X head74 x are fixed apart by a predetermined spacing in the X-axis direction,in a state each facing scales 2072. That is, X head 74 x and Y head 74 yfacing the first grating group and X head 74 x and Y head 74 y facingthe second grating group each irradiates scales 2072 with a measurementbeam at a spacing larger than the spacing between adjacent grating areasof scales 2072. In the description below, for convenience ofexplanation, X head 74 x and Y head 74 y that one of the head bases 88has will be referred to as head 74 a and head 74 b, and Y head 74 y andX head 74 x that the other head base 88 has will be referred to as head74 c and head 74 d, respectively.

In this case, head 74 a and head 74 c are arranged at the same Xposition (on the same straight line parallel to the Y-axis direction),and head 74 b and head 74 d are arranged at the same X position (on thesame straight line parallel to the Y-axis direction) different from theX position of head 74 a and head 74 c. Heads 74 a, 74 d and thetwo-dimensional gratings RG that face each head structure a pair of Xlinear encoders, and heads 74 b, 74 c and the two-dimensional gratingsRG that face each head structure a pair of Y linear encoders.

With the liquid crystal exposure apparatus according to the twentiethembodiment, the structure of other parts including the remaining part ofhead base 88 is similar to liquid crystal exposure apparatus 10according to the first embodiment described earlier, except for thedrive control (position control) of substrate holder 32 using substratemeasurement system 2070 by main controller 100.

With the liquid crystal exposure apparatus according to the twentiethembodiment, position measurement of substrate holder 32 can be performedby heads 74 a to 74 d of the pair of head bases 88, that is, by the pairof X linear encoders and the pair of Y linear encoders, between a firstposition where the pair of head bases 88 faces the +X edge of scale base84 as is shown in FIG. 72A, and a second position where the pair of headbases 88 faces the −X edge of scale base 84 as is shown in FIG. 72B,within a range where substrate holder 32 moves in the X-axis direction.FIG. 72A shows a state in which only head 74 b faces none of the scales2072, and FIG. 72B shows a state in which only head 74 c faces none ofthe scales 2072.

In the process of substrate holder 32 moving in the X-axis directionbetween the first position shown in FIG. 72A and the second positionshown in FIG. 72B, positional relation between the pair of head bases 88and scales 2072 changes between five states; a first to fourth stateshown respectively in FIGS. 73A to 73D and a fifth state in which fourheads 74 a to 74 d all face the two-dimensional grating RG of either oneof the scales 2072 (that is, all four heads 74 a to 74 d irradiatetwo-dimensional grating RG with measurement beams). In the descriptionbelow, instead of saying that the head faces two-dimensional grating RGof scales 2072 or two-dimensional grating RG of scales 2072 isirradiated with the measurement beam, the expression, the head faces thescale, will simply be used.

Here, for convenience of explanation, six scales 2072 will be picked,and to identify each scale, reference codes a to f will be used and thescales will be described as scales 2072 a to 2072 f (refer to FIG. 73A).

The first state in FIG. 73A shows a state in which head 74 a faces scale2072 b, heads 74 c and 74 d face scale 2072 e, and only head 74 b facesneither of the scales, and the second state in FIG. 73B shows a state inwhich substrate holder 32 moves by a predetermined distance in the −Xdirection from the state shown in FIG. 73A so that heads 74 a and 74 bface scale 2072 b, head 74 d faces scale 2072 e, and only head 74 c nolonger faces any of the scales. In the process of the state changingfrom the state shown in FIG. 73A to the state shown in FIG. 73B, thechange goes through the fifth state in which heads 74 a and 74 b facescale 2072 b and heads 74 c and 74 d face scale 2072 e.

The third state in FIG. 73C shows a state in which substrate holder 32moves by a predetermined distance in the −X direction from the stateshown in FIG. 73B so that only head 74 a no longer faces any of thescales. In the process of the state changing from the state shown inFIG. 73B to the state shown in FIG. 73C, the change goes through thefifth state in which heads 74 a and 74 b face scale 2072 b, head 74 cfaces scale 2072 d, and head 74 d faces scale 2072 e.

The fourth state in FIG. 73D shows a state in which substrate holder 32moves by a predetermined distance in the −X direction from the stateshown in FIG. 73C so that only head 74 d no longer faces any of thescales. In the process of the state changing from the state shown inFIG. 73C to the state shown in FIG. 73D, the change goes through thefifth state in which head 74 a faces scale 2072 a, head 74 b faces scale2072 b, head 74 c faces scale 2072 d, and head 74 d faces scales 2072 e.

When substrate holder 32 moves by a predetermined distance in the −Xdirection from the state shown in FIG. 73D, after the process goesthrough the fifth state in which head 74 a faces scale 2072 a, head 74 bfaces scale 2072 b, and heads 74 c and 74 d face scale 2072 d, then, thestate moves into the first state in which head 74 a faces scale 2072 a,heads 74 c and 74 d face scale 2072 d, and only head 74 b faces neitherof the scales.

While the description so far is about the change of state (positionalrelation) between each of the three scales 2072 of the five scales 2072arranged on both the +Y side and the −Y side of substrate holder 32 andthe pair of head bases 88, also between 10 scales 2072 and the pair ofhead bases 88, regarding each of the adjacent three scales 2072 of thefive scales 2072 arranged on both the +Y side and the −Y side ofsubstrate holder 32, the positional relation with the pair of head bases88 changes in a similar order as is described above.

As is described so far, in the twentieth embodiment, even if substrateholder 32 is moved in the X-axis direction, at least three out of thetotal of four heads; the two X heads 74 x, namely heads 74 a and 74 d,and two Y heads 74 y, namely heads 74 b and 74 c, constantly face anyone of scales 2072 (two-dimensional grating RG). Moreover, even ifsubstrate holder 32 is moved in the Y-axis direction, since the width ofthe grating area of scales 2072 is set so that for all four heads, themeasurement beams in the Y-axis direction do not move off from scales2072 (two-dimensional grating RG), at least three of the four heads faceany one of scales 2072 at all times. Accordingly, main controller 100can control position information on substrate holder 32 in the X-axisdirection, the Y-axis direction, and the θz direction, at all times,using three heads of heads 74 a to 74 d. This point will be describedfurther below.

When measurement values of X head 74 x and Y head 74 y are to be CX andCY, measurement values C_(X) and C_(Y) can each be expressed by thefollowing formulas, (1a) and (1b).

C _(X)=(p _(i) −X) cos θz+(q _(i) −Y) sin θz   (1a)

C _(Y)=−(p _(i) −X)sin θz+(q _(i) −Y)cos θz   (1b)

Here, X, Y, and θx show the position of substrate holder 32 in theX-axis direction, the Y-axis direction, and the θz direction,respectively. Also, p_(i) and q_(i) are the X position (X coordinatevalue) and the Y position (Y coordinate value) of each of the heads 74 ato 74 d. In the embodiment, the X coordinate values p_(i) and the Ycoordinate values q_(i) (i=1, 2, 3, 4) of each of the heads 74 a, 74 b,74 c, and 74 d is calculated from measurement results output from eachpair of X heads 80 x and Y heads 80 y and the corresponding scale 78,and from relative positional relation between head base 1996 and scale72.

Accordingly, when substrate holder 32 and the pair of head bases 88 havea positional relation as is shown in FIG. 72A and the position ofsubstrate holder 32 at this time within the XY plane in directions ofthree degrees of freedom is (X, Y, θz), then measurement values of thethree heads 74 a, 74 c, and 74 d can theoretically be expressed by thefollowing formulas, (2a) to (2c) (also called an affine transformationrelation).

C ₁=(p ₁ −X) cos θz+(q ₁ −Y) sin θz   (2a)

C ₃=−(p ₃ −X) sin θz+(q ₃ −Y) cos θz   (2b)

C ₄=(p ₄ −X) cos θz+(q ₄ −Y) sin θz   (2c)

In a reference state where substrate holder 32 is at a coordinate origin(X, Y, θz)=(0, 0, 0), by simultaneous equations (2a) to (2c), C₁=p₁,C₃=q₃, and C₄=p₄. The reference state, for example, is a state in whichthe center of substrate holder 32 (almost coincides with the center ofsubstrate P) coincides with the center of the projection area byprojection optical system 16 and the θz rotation is zero. Accordingly,in the reference state, the Y position of substrate holder 32 can alsobe measured by head 74 b, and measurement value C₂ by head 74 b,according to formula (1b), is C₂=q₂.

Accordingly, when the measurement values of the three heads 74 a, 74 c,and 74 d are to be initially set to p₁, q₃, and p₄ in the referencestate, hereinafter, the three heads 74 a, 74 c, and 74 d are to presenttheoretical values given by the formulas (2a) to (2c) with respect todisplacements (X, Y, θz) of substrate holder 32.

Note that in the reference state, instead of one of the heads 74 a, 74c, and 74 d, such as for example, instead of 74 c, measurement value C₂of head 74 b may be initially set as q₂.

In this case, hereinafter, the three heads 74 a, 74 b, and 74 d are topresent theoretical values given by the formulas (2a), (2c), and (2d)with respect to displacements (X, Y, θz) of substrate holder 32.

C ₁=(p ₁ −X) cos θz+(q ₁ −Y) sin θz   (2a)

C ₄=(p ₄ −X) cos θz+(q ₄ −Y) sin θz   (2c)

C ₂=−(p ₂ −X)sin θz+(q ₂ −Y)cos θz   (2d)

In simultaneous equations (2a) to (2c) and simultaneous equations (2a),(2c), and (2d), three formulas are given with respect to three variables(X, Y, θz). Therefore, conversely, if dependent variables C₁, C₃, and C₄in simultaneous equations (2a) to (2c), or dependent variables C₁, C₄,and C₂ in simultaneous equations (2a), (2c), and (2d) are given,variables X, Y, and θcan be obtained. Here, the equations can be solvedeasily when an approximate sin Γz≈θz is applied, or when a higherapproximate is applied. Accordingly, positions (X, Y, θz) of substrateholder 32 can be calculated from measurement values C₁, C₃, and C₄ (orC₁, C₂, and C₄) of heads 74 a, 74 c, and 74 d (or heads 74 a, 74 b, and74 d).

Next, a linkage process, namely, initial setting of measurement values,at the time when switching heads of substrate measurement system 2070that measures position information on substrate holder 32 performed inthe liquid crystal exposure apparatus according to the twentiethembodiment, will be described centering on the operation of maincontroller 100.

In the twentieth embodiment, three encoders (X heads and Y heads) areconstantly measuring the position information on substrate holder 32 asis previously described in an effective stroke range of substrate holder32, and on performing the switching process of the encoders (X head or Yhead), for example, as is shown in FIG. 74B, each of the four heads 74 ato 74 d face any of the scales 2072 and moves into a state (the fifthstate described earlier) so that the position of substrate holder 32 canbe measured. FIG. 74B shows an example of the fifth state that appearsduring the change of state from the state shown in FIG. 74A in whichfrom measuring the position of substrate holder 32 with heads 74 a, 74b, and 74 d, substrate holder 32 moves in the −X direction, and then asis shown in FIG. 74C, moves to a state in which the position ofsubstrate holder 32 is measured with heads 74 b, 74 c, and 74 d. Thatis, FIG. 74B shows a state in which the three heads used for measuringposition information on substrate holder 32 are being switched, fromheads 74 a, 74 b, and 74 d to heads 74 b, 74 c, and 74 d.

At the moment when the switching process (linkage) of heads (encoders)used for position control (measurement of position information) ofsubstrate holder 32 within the XY plane is to be performed, heads 74 a,74 b, 74 c, and 74 d are facing scales 2072 b, 2072 b, 2072 d, and 2072e, respectively, as is shown in FIG. 74B. When taking a look at FIGS.74A to 74C, it may appear that head 74 a is about to be switched to head74 c in FIG. 74B, however, as it is obvious from the point that themeasurement direction is different in head 74 a and head 74 c, it ismeaningless to give the measurement value (count value) of head 74 awithout any changes to head 74 c as an initial value of the measurementvalue at the timing when linkage is performed.

Therefore, in the embodiment, main controller 100 is to performswitching from the measurement of position information (and positioncontrol) on substrate holder 32 using the three heads 74 a, 74 b, and 74d to the measurement of position information (and position control) onsubstrate holder 32 using the three heads 74 b, 74 c, and 74 d. That is,this method is different from the concept of a normal encoder linkageand does not link one head to another head, but is a method of linking acombination of three heads (encoders) to another combination of threeheads (encoders).

Main controller 100, first of all, solves simultaneous equations (2a),(2c), and (2d) based on measurement values C₁, C₄, and C₂ of heads 74 a,74 d, and 74 b, and calculates position information (X, Y, θz) on thesubstrate holder within the XY plane.

Next, main controller 100 substitutes X and θz calculated above into thefollowing affine transformation formula (formula (3) below), and obtainsthe initial value (the value that should be measured by head 74 c) ofthe measurement value of head 74 c.

C ₃=−(p ₃ −X) sin θz+(q ₃ −Y) cos θz   (3)

In formula (3) above, p₃ is the X coordinate value and q₃ is the Ycoordinate value of head 74 c. In the embodiment, X coordinate value p₃and Y coordinate value q₃, as is described earlier, are calculated frommeasurement results output from each pair of X heads 80 x and Y heads 80y and the corresponding scale 78, and from relative positional relationbetween head base 1996 and scale 72.

By giving initial value C₃ described above as the initial value of head74 c, linkage is to be completed without contradictions whilemaintaining the positions (X, Y, θz) of substrate holder 32 indirections of three degrees of freedom. Thereinafter, positioncoordinates (X, Y, θz) of substrate holder 32 is calculated by solvingthe following simultaneous equations (2b) to (2d), using the measurementvalues C₂, C₃, and C₄ of heads 74 b, 74 c, and 74 d which are to be usedafter the switching.

C ₃=−(p ₃ −X) sin θz+(q ₃ −Y) cos θz   (2b)

C ₄=(p ₄ −X) cos θz+(q ₄ −Y) sin θz   (2c)

C ₂=−(p ₂ −X) sin θz+(q ₂ −Y) cos θz   (2d)

Note that while the case has been described above when the switching isfrom three heads to another three heads including one head differentfrom the three heads, it was described in this way because the value tobe measured using the another head after switching is calculated basedon the principle of affine transformation using the position (X, Y, θz)of substrate holder 32 obtained from the measurement values of the threeheads used before switching, and the value that has been calculated isto be set as an initial value of the another head used after switching.However, when focusing only on the two heads serving as direct targetsof switching and linkage process without referring to the procedure ofcalculation and the like of the values to be measured using the anotherheads used after switching, it may also be said that one head of thethree heads used before switching is switched to a different head. Inany case, the switching of the heads is performed in a state where bothof the head used for measuring position information and position controlof the substrate holder before switching and the head to be used afterswitching simultaneously face any of the scales 2072.

Note that while the description above is an example of switching ofheads 74 a to 74 d, in switching from any three heads to another threeheads, or switching from one of the heads to another head, switching ofheads is performed in a procedure similarly to the procedure describedabove.

In the case the grating section is structured with a plurality of scales(two-dimensional gratings RG) as in the twentieth embodiment, ameasurement error occurs in the encoder system when the scales, or morestrictly speaking, the grating (two-dimensional grating RG) formed oneach of the scales irradiated with the measurement beams are mutuallyshifted.

Also, in the twentieth embodiment, combination of at least two scales2072 irradiated with measurement beams of at least three heads used forposition information measurement and position control of substrateholder 32 is different, depending on the X position of substrate holder32, and it can be considered that a coordinate system exists for eachcombination of these at least two scales, therefore, when a displacement(grid error) between these coordinate systems occur, for example, due torelative position variation between at least two scales, a measurementerror occurs in the encoder system. Note that since the relativeposition variation between at least two scales changes over a longperiod of time, grid errors, that is, measurement errors are to vary aswell.

However, in the twentieth embodiment, on switching the heads, at thepoint when setting the initial value of the head used after theswitching, the fifth state occurs in which the four heads 74 a to 74 dall simultaneously face either one of at least two scales 2072. In thisfifth state, while position information on substrate holder 32 can bemeasured with all four heads, since only three heads are necessary tomeasure the position coordinates (X, Y, θz) of the substrate holder, onehead becomes redundant. Therefore, main controller 100, by using themeasurement value of this redundant head, is to acquire correctioninformation (grid correction information or grating correctioninformation) of the measurement error of the encoder system due todisplacement (grid error) between coordinate systems, and to move(perform position control of) substrate holder 32 so that themeasurement error of the encoder system due to grid error iscompensated.

For example, measurement is performed of the position coordinates (X, Y,θz) of the substrate holder by two sets of the heads in a set of threewhen each of the four heads 74 a to 74 d simultaneously face at leasttwo scales, and namely, offsets Δx, Δy, and Δθz obtained from themeasurement, specifically, differences of positions (X, Y, θz) obtainedby solving the simultaneous equations using the affine transformationformula described earlier, are obtained, and these offsets are to serveas offsets of the coordinate system consisting of the combination of atleast two scales that the four heads 74 a to 74 d are facing. Thisoffset is used in measurement of position information on substrateholder 32 and in controlling the position of substrate holder 32 bythree heads among the four heads facing the at least two scales. Notethat before and after the time when switching and linkage process of theheads described earlier are performed, since the combination of at leasttwo scales that the three heads used for measuring position informationand for controlling the position of substrate holder 32 face beforeswitching, and the combination of at least two scales that the threeheads used for measuring position information and for controlling theposition of substrate holder 32 face after switching are naturallydifferent, different offsets are used as grid or grating correctioninformation on measuring position information and on controlling theposition of substrate holder 32 before and after switching of the heads.

Here, as an example, the fifth state below (called a state of case 1)will be considered that appears just before the state shown in FIG. 74A,during the process when substrate holder 32 is moving in the −Xdirection. That is, a state in which heads 74 a and 74 b face scale 2072b, and heads 74 c and 74 d face scale 2072 e. In this state, of heads 74a to 74 d, offsets can be obtained using two sets of heads consisting ofa combination of any three heads. However, in the state shown in FIG.74A, head 74 c can no longer be used for measurement, and to restore themeasurement by this head 74 c, position coordinates (X, Y, θz) of thesubstrate holder calculated from the measurement values of the threeheads 74 a, 74 b, and 74 d are used in the fifth state shown in FIG.74B. Also, during the process when substrate holder 32 is moving in the+X direction, prior to the state of case 1, head 66 b being in anon-measurable state is restored. On restoring this head 74 b, positioncoordinates (X, Y, θz) of the substrate holder calculated from themeasurement values of the three heads 74 a, 74 c, and 74 d are used.Therefore, in the state of case 1, grating correction information on thecoordinate system consisting of a combination of scales 2072 b and 2072e is to be acquired, using the set of three heads excluding the set ofthree heads 74 a, 74 b, and 74 d and the set of three heads 74 a, 74 c,and 74 d; that is, using the set of three heads 74 a, 74 b, and 74 c andthe set of three heads 74 b, 74 c, and 74 d.

Specifically, main controller 100, in the state of case 1, calculatesthe position coordinates (for convenience, (X₁, Y₁, θz₁)) of substrateholder 32 using the measurement values of heads 74 a, 74 b, and 74 c,along with calculating the position coordinates (for convenience, (X₂,Y₂, θz₂)) of substrate holder 32 using the measurement values of heads74 b, 74 c, and 74 d. And, differences between two positions ΔX=X₂−X₁,ΔY=Y₂−Y₁, and Δθz=Δθz₁−Δθz₂ are obtained, and these offsets are storedas grating correction information in, e.g. an internal memory (storagedevice).

Also, for example, in the fifth state shown in FIG. 74B, the heads usedfor position control of substrate holder 32 is switched from head 74 ato head 74 c, and on this switching, the position coordinates ofsubstrate holder 32 are calculated by the affine transformation formuladescribed earlier using the measurement values of the three heads 74 a,74 b, and 74 d. On this operation, along with this calculation of theposition coordinates, main controller 100, excluding, for example, theset of three heads 74 a, 74 b, and 74 d used for calculating theposition coordinates of substrate holder 32 for switching the heads andthe set of three heads 74 b, 74 c, and 74 d used for setting themeasurement values of the heads after switching at the time of the nextswitching of the heads, acquires grating correction information(offsets) of a coordinate system consisting of a combination of threescales 2072 b, 2072 d, and 2072 e that heads 74 b, 74 c, and 74 d usedfor position measurement and position control of substrate holder 32after the switching of heads described above face, using, e.g., the setof three heads 74 a, 74 b, and 74 c, and the set of three heads 74 a, 74b, and 74 d, similarly to the combination of scales 2072 b and 2072 e.

In the embodiment, main controller 100 obtains offsets ΔX, ΔY, and Δθzin the procedure described above for a plurality of coordinate systemscorresponding to all combinations of at least two scales 2072 that thethree heads used for position control of substrate holder 32 that aresequentially switched in the process of substrate holder 32 moving inthe −X direction or the +X direction from the first position shown inFIG. 72A to the second position shown in FIG. 72B face, and stores theoffsets as grating correction information in the storage device.

Also, for example, main controller 100, after performing switching ofthe heads and the linkage process described earlier in the fifth statein which heads 74 a and 74 b face scale 2072 b and heads 74 c and 74 dalso face 2072 e in the process of the state changing from the firststate shown in FIG. 73A to the second state shown in FIG. 73B, mayacquire the grating correction information (offsets) of a coordinatesystem consisting of scale 2072 b and scale 2072 e in the proceduredescribed above at a plurality of positions while substrate holder 32 isbeing moved until head 74 c becomes non-measurable, using themeasurement values of the three heads 74 a, 74 b, and 74 d for positioncontrol which include head 74 b that has been restored. That is, foreach combination of at least two scales 2072 that the three heads usedfor position measurement and position control of substrate holder 32face, not only one grating correction information but a plurality ofgrating correction information may be acquired. Also, while four heads,including the three heads used for position measurement and positioncontrol of substrate holder 32 and the redundant head, are facing atleast two scales 2072 of the same combination, grating correctioninformation may be acquired substantially continuously, using the methoddescribed above. In this case, grating correction information can beacquired covering the whole area in the period (section) when the fourheads face at least two scales 2072 of the same combination. Note thatthe number of grating correction information acquired for eachcombination of at least two scales 2072 that the three heads used forposition measurement and position control of substrate holder 32 facedoes not have to be the same, and the number of grating correctioninformation to be acquired may be different depending on the combinationof scales. For example, the number of grating correction information maybe different in the combination of at least two scales 2072 that thethree heads face on exposure operation and the combination of at leasttwo scales 2072 that the three heads face on operations other than theexposure operation (such as alignment operation and substrate exchangeoperation). Also, in the embodiment, as an example, before loading thesubstrate on substrate holder 32, or after loading the substrate andbefore the substrate processing operation (including operations such asexposure operation and alignment operation), grating correctioninformation is to be acquired for all combinations of at least twoscales 2072 that the three heads used for position measurement andposition control of substrate holder 32 face and is to be stored in thestorage device, and the grating correction information is to be updatedregularly or as needed. Update of the grating correction information,for example, may be performed at any timing including during thesubstrate processing operation, as long as the substrate processingoperation can be performed.

Note that once after all necessary grating correction information(offsets ΔX, ΔY, and Δθz) is acquired, actually, offsets ΔX, ΔY, and Δθzmay be updated each time switching of the heads is performed, however,this is not always required, and offsets ΔX, ΔY, and Δθz may be updatedat an interval determined in advance, such as each time switching of theheads is performed a predetermined number of time, or each time exposureis completed on a predetermined number of substrates. The offsets may beacquired or updated during the period when switching of the heads is notperformed. Also, the update of offsets described above may be performedbefore the exposure operation, or if necessary, during the exposureoperation.

Note that instead of correcting the measurement information (positioncoordinates) of substrate measurement system 2070 using each offsetdescribed above, for example, target values for position setting orposition control on moving substrate holder 32 may be corrected, and inthis case, position error (position error caused by grid error generatedin the case correction of target values has not been performed) ofsubstrate holder 32 can be compensated.

Now, in the encoder system using a scale (grating area) and a head, itis known that a measurement error occurs due to the scale or the head,or relative movement of the scale and the head in a direction other thanthe measurement direction (non-measurement direction). As measurementerrors occurring due to scales (hereinafter called error caused byscales), there are measurement errors caused by deformation,displacement, flatness, or error in formation and the like of thegrating area formed on the scale. Also, as errors occurring due to heads(hereinafter called error caused by heads), measurement errors caused bydisplacement of heads (including rotation, tilt and the like other thandisplacement of measurement direction) or optical properties can begiven. Other than these errors, errors are known to be caused by notmeeting Abbe conditions.

In the liquid crystal exposure apparatus according to the twentiethembodiment, correction information is used to compensate for measurementerrors of the encoder system like the ones described above. Here, ifmeasurement error of the encoder is obtained, then the measurement errorcan be used as it is as correction information.

First of all, measurement error of an encoder system (hereinafter calledholder encoder system) structured from two each of heads 74 a, 74 b and74 c, 74 d provided at the lower end side of the pair of head bases 88and scales 2072 facing these heads will be described.

Error Caused by Scales

Correction Information of Measurement Error Caused by Unevenness(Flatness) of Scales

In the case the optical axis of each head of the holder encoder systemalmost coincides with the Z-axis, and the pitching amount, rollingamount, and the yawing amount of substrate holder 32 is all zero,measurement errors due to the attitude of substrate holder 32 are notsupposed to occur in each encoder. However, measurement errors in eachof the encoders are not actually zero even in such a case. This isbecause the grating surface (e.g., the surface) of scales 2072 is not anideal plane, and is more or less uneven. When the grating surface of thescale is uneven, the grating surface of the scale is displaced(vertically moves) in the Z-axis direction or tilts with respect to theheads even when substrate holder 32 moves in parallel with the XY plane.This consequently is no other than a relative movement occurring in thenon-measurement direction between the heads and the scales, and suchrelative movement becomes a cause of measurement errors, as is describedearlier.

Therefore, in the liquid crystal exposure apparatus according to thetwentieth embodiment, for example, at the time of maintenance and thelike, main controller 100 moves stage main section 34 to which substrateholder 32 is fixed (hereinafter shortly referred to as “substrate holder32” as appropriate) in the +X direction or the −X direction, whilemeasuring the X position of substrate holder 32 with a measurementdevice serving as a reference for measurement such as an interferometersystem, in a state where the pitching amount, the rolling amount, andthe yawing amount of substrate holder 32 are all zero. To achieve suchmeasurement, in the embodiment, reflection members of a required numberhaving reflection surfaces of a predetermined area with high flatnessare attached to substrate holder 32 at the time of maintenance and thelike. The embodiment is not limited to this, and assuming the use of theinterferometer system, the reflection surfaces of a predetermined areawith high flatness may be formed in advance at a predetermined positionat each end surface of substrate holder 32.

During the movement of substrate holder 32 in the X-axis directiondescribed above, main controller 100 performs measurement of the Zposition of the surface of scales 2072 using a sensor having highmeasurement resolution, takes in the measurement values of the sensorand the measurement values of the interferometer system at apredetermined sampling interval, and then stores the measurement valuesin a storage device. Here, the movement of substrate holder 32 ispreferably performed at a speed low enough so that the measurementerrors due to air fluctuation of the interferometer system can beignored. Then, based on each measurement value taken in, main controller100 obtains a relation between the measurement values of the sensor andthe measurement values of the interferometer As this relation, forexample, a function Z=f_(i) (x) that expresses unevenness of a scalegrating surface (the grating surface of two-dimensional grating RG) canbe obtained. Here, x is the X position of substrate holder 32 measuredby the interferometer. Note that in the case the unevenness of the scalegrating surface has to be obtained as a function of x, y, for example,moving and positioning substrate holder 32 in the Y-axis direction by apredetermined pitch based on measurement values of Y head 74 y, andtaking in measurement values of the interferometer and measurementvalues of the sensor simultaneously while substrate holder 32 is beingmoved in the X-axis direction as is described above, may be repeated foreach positioning position. This allows function Z=g_(i) (x,y) thatexpresses the unevenness of scale 2072 surface to be obtained Here, _(i)is a number used to identify the plurality of scales 2072.

Note that as is disclosed in, for example, U.S. Pat. No. 8,675,171, theholder encoder system itself may be used to obtain function Z=f_(i)(x)or Z=g_(i)(x, y) expressing the unevenness of the scale grating surface.Specifically, function Z=f_(i)(x) or Z=g_(i)(x, y) expressing theunevenness of the scale grating surface may be obtained, by performingan operation of finding a point not sensitive to tilt operation ofsubstrate holder 32, that is, finding a singular point where measurementerror of the encoder becomes zero regardless of the tilt angle ofsubstrate holder 32 with respect to the XY plane for one of the encoderheads of the holder encoder system in the method disclosed in the U.S.Patent described above, on a plurality of measurement points on thescale. Note that the unevenness information on the scale grating surfaceis not limited to a function, and may be stored in the form of a map.Here, the “a singular point where measurement error of the encoderbecomes zero regardless of the tilt angle of substrate holder 32 withrespect to the XY plane” is exactly the intersection point (point shownby a black circle) of many straight lines of the graph shown in FIG. 77.That is, obtaining the Z position (Z coordinate value) of this singularpoint for the entire scale grating surface means none other than toobtain the unevenness of the scale grating surface.

Correction Information of Grating Pitch of Scales and CorrectionInformation of Grating Deformation

With scales of the encoder, diffraction grating deforms by thermalexpansion and the like or the pitch of the diffraction grating changespartially or as a whole with the lapse of using time, and lacks inlong-term stability mechanically. Therefore, errors included in themeasurement values become larger with the lapse of using time, whichhave to be corrected.

Correction information on the grating pitch of the scale and correctioninformation on grating deformation are obtained as follows, for example,at the time of maintenance and the like of the liquid crystal exposureapparatus. Prior to this acquiring operation, measurement of unevennessfor the grating surface of each scale described above is performed, andfunction Z=f_(i)(x) or Z=g_(i)(x, y) expressing the unevenness of thescale grating surface is to be stored in the storage device.

Main controller 100, first of all, loads function Z=f_(i) (x) orZ=g_(i)(x, y) stored in the storage device, into an internal memory.

Next, main controller 100 moves substrate holder 32 in the +X directionor the −X direction, while measuring the X position of substrate holder32 with the interferometer system described earlier, in a state wherethe pitching amount, the rolling amount, and the yawing amount ofsubstrate holder 32 are all maintained to zero. This movement ofsubstrate holder 32 is also preferably performed at a speed low enoughso that the measurement errors due to air fluctuation of theinterferometer system can be ignored. During this movement, maincontroller 100, while correcting measurement values (output) of an Xlinear encoder (hereinafter shortly referred to as X encoder asappropriate) structured by head 74 a and scale 2072 subject toacquisition using the function Z=f_(i)(x) described above, takes in themeasurement values after correction and the measurement values of theinterferometer at a predetermined sampling interval, and obtains arelation between measurement values (measurement values corresponding tooutput of X encoder−function f_(i)(x)) of X linear encoder andmeasurement values of the interferometer, based on each measurementvalue taken in. That is, in this manner, main controller 100 obtainsgrating pitch (spacing between adjacent grid lines) of a diffractiongrating (X diffraction grating) whose periodic direction is in theX-axis direction of two-dimensional grating RG of scales 2072 arrangedsequentially facing head 74 a with the movement of substrate holder 32,and the correction information on the grating pitch. As this correctioninformation on the grating pitch, for example, in the case thehorizontal axis is measurement values of the interferometer and thevertical axis is measurement values of the encoder (measurement valueswhose errors caused by unevenness of the scale surface have beencorrected), a correction map and the like can be obtained showing arelation between measurement values in a curved line.

In the case of acquiring the grating pitch and the correctioninformation on the grating pitch described above for adjacent pluralityof scales 2072 structuring the first grating group, after themeasurement beam from head 74 a no longer hits the first scale 2072, atthe point when the measurement beam begins to hit the adjacent scale andoutput of detection signals from the head is resumed, initial values ofmeasurement values of X linear encoder structured by head 74 a and scale2072 subject to acquisition are set to the measurement values of theinterferometer at that point, and then measurement of the adjacentscales 2072 begins. Measurement of scales 2072 in a row structuring thefirst grating group is performed in the manner described.

For each scale 2072 structuring the second grating group as well, thegrating pitch and the correction information on the grating pitch isacquired similarly to the description above (however, using head 74 dinstead of head 74 a).

Concurrently with acquiring the correction information on the gratingpitch described above, measurement values of head 74 b and measurementvalues of the interferometer are taken in at a predetermined samplinginterval, and a relation between measurement values of head 74 b andmeasurement values of the interferometer may be obtained, based on eachmeasurement value taken in. On taking in the measurement values of head74 b, the measurement is started with an initial value of head 74 b (Ylinear encoder (hereinafter shortly referred to as Y encoder asappropriate) structured by head 74 b and an opposing scale 2072) beingset to a predetermined value, e.g., zero. This allows grid line curveand correction information on the grid line curve to be obtained of adiffraction grating (Y diffraction grating) whose periodic direction isin the Y-axis direction of two-dimensional grating RG of scale 2072 thathead 74 b faces. As the correction information on this grid line curve,for example, in the case the horizontal axis is measurement values ofthe interferometer and the vertical axis is measurement values of head74 b, a correction map and the like can be obtained showing a relationbetween the measurement values in a curved line. In the case ofacquiring the correction information on the grid line curve describedabove for adjacent plurality of scales 2072 structuring the firstgrating group, after the measurement beam from head 74 b no longer hitsthe first scale 2072, at the point when the measurement beam begins tohit the adjacent scale and output of detection signals from the head isresumed, initial values of measurement values of head 74 b are set to apredetermined value, e.g. zero, and then the measurement is resumed.

For each scale 2072 structuring the second grating group as well, thecorrection information on the grid line curve is acquired similarly tothe description above (however, using head 74 c instead of head 74 b).Note that the correction information may be acquired based on gratinginformation (pitch, deformation and the like) obtained by imagingtwo-dimensional grating RG of each scale.

Measurement Error Caused by Relative Movement of Heads and Scales in theNon-measurement Direction

Now, when substrate holder 32 moves in a direction different from themeasurement direction, e.g. the X-axis direction (or the Y-axisdirection), and a relative movement occurs in a direction other than thedirection to be measured (relative movement in a non-measurementdirection) between head 74 x (or head 74 y) and scale 2072, in mostcases, measurement errors occur in the X encoder (or the Y encoder).

Therefore, in the embodiment, correction information for correcting themeasurement errors of each encoder caused by relative movement betweenthe heads and the scales in the non-measurement direction describedabove, is acquired, for example, at the start-up of the exposureapparatus, or at the time of maintenance in the following manner.

a. First of all, main controller 100 moves substrate holder 32 viasubstrate drive system 60, while monitoring measurement values of ameasurement system different from the encoder system subject toacquisition of correction information, such as the measurement values ofthe interferometer system described earlier, and makes head 74 a face anarbitrary area (called calibration area for convenience) of an arbitraryscale 2072 of the first grating group.

b. Then, main controller 100 drives substrate holder 32 so that rollingamount θx and yawing amount θz of substrate holder 32 both becomes zeroand the pitching amount θy becomes a desired amount α₀ (here, α₀0=200μrad), based on the measurement values of the interferometer system, andafter this movement, head 74 a irradiates the calibration area of scale2072 with the measurement beam, and measurement values corresponding tophoto-electrically converted signals from head 74 a receiving thereflection beams are stored in the internal memory.

c. Next, main controller 100, while maintaining the attitude (pitchingamount θy=α₀, yawing amount θz=0, rolling amount θx=0) of substrateholder 32, based on the measurement values of the interferometer system,moves substrate holder 32 within a predetermined range such as forexample, within the range of −100 μm to +100 μm in the Z-axis direction,and during this movement, sequentially takes in measurement valuescorresponding to photo-electrically converted signals from head 74 areceiving the reflection beams are stored in the internal memory, whileirradiating calibration area of scale 2072 with a detection beam fromhead 74 a at a predetermined sampling interval. Note that on themeasurement described above, position of substrate holder 32 in theZ-axis direction, the θx direction, and θy direction can be measuredwith Z-tilt position measurement system.

d. Next, main controller 100 changes pitching amount θy of substrateholder 32 to (α=α₀−Δα), based on the measurement values of theinterferometer system.

e. Next, an operation similar to paragraph c. described above isrepeatedly performed on the attitude after the change.

f. Then, operations described in d. and e. are alternately repeated, andfor the range in which pitching amount θy is, for example, −200μrad<θx<+200 μrad, Δα (rad), measurement values of head 74 a within theZ drive range described above are take in, for example, at a 40 μradinterval.

g. Next, by plotting each data in the internal memory obtained by theprocessing described above in paragraphs b. to e. on a two-dimensionalcoordinate system whose horizontal axis shows the Z position andvertical axis shows the encoder count value, sequentially connectingplot points having the same pitching amount, and shifting the horizontalaxis in the vertical axis direction so that the line (horizontal line inthe center) when the pitching amount is zero passes the origin, thegraph in FIG. 77 showing change characteristics of measurement values ofthe encoder (head) corresponding to the Z leveling of substrate holder32 can be obtained.

The value of the vertical axis at each point on the graph shown in FIG.77 is none other than the measurement error of the encoder at each Zposition when pitching amount θy=α. Therefore, main controller 100 usespitching amount θy, Z position, and encoder measurement error at eachpoint on this graph as table data, and the table data is stored inmemory as correction information on error caused by holder position ofthe X encoder structured by head 74 a and X diffraction grating of scale2072. Or, main controller 100 may assume that the measurement error is afunction of Z position z and pitching amount θy, and obtains thefunction, for example, by calculating an unfixed coefficient by theleast squares method, and the function is stored in the storage deviceas correction information on error caused by holder position.

h. Next, main controller 100 moves substrate holder 32 via substratedrive system 60 while monitoring the measurement values theinterferometer system, and makes head 74 d (another X head 74 x) face anarbitrary area (calibration area) of an arbitrary scale 2072 of thesecond grating group.

i. Then, main controller 100 performs processing similar to thedescription above on head 74 d, and stores the correction information onthe X encoder structured by head 74 d and the X diffraction grating ofscale 2072 in the storage device.

j. Hereinafter, correction information on the Y encoder structured byhead 74 b and the Y diffraction grating of an arbitrary scale 2072 ofthe first grating group and correction information on the Y encoderstructured by head 74 c and the Y diffraction grating of an arbitraryscale 2072 of the second grating group are obtained similarly, andstored in the storage device.

Next, main controller 100 sequentially changes the yawing amount θz ofsubstrate holder 32 in the range of −200 μrad<θz<+200 μrad whilemaintaining both the pitching amount and rolling amount of substrateholder 32 to zero in a procedure similar to the case of changing thepitching amount as is described above, and at each position, movessubstrate holder 32 within a predetermined range such as, for example,the range of −100 μm to +100 μm in the Z-axis direction, and during themovement, takes in measurement values of the head at a predeterminedsampling interval, and stores the values in the internal memory. Such ameasurement is performed for all heads 74 a to 74 d, and in a proceduresimilar to the procedure described earlier, by plotting each data in theinternal memory on a two-dimensional coordinate system whose horizontalaxis shows the Z position and vertical axis shows the encoder countvalue, sequentially connecting plot points having the same pitchingamount, and shifting the horizontal axis in the vertical axis directionso that the line (horizontal line in the center) when the pitchingamount is zero passes the origin, a graph similar to the one in FIG. 77is obtained. Then, main controller 100 uses the yawing amount θz, Zposition z, and measurement error at each point on the graph similar tothe one in FIG. 77 as table data, and the table data is stored in thestorage device as correction information. Or, main controller 100 mayassume that the measurement error is a function of Z position z andyawing amount θz, and obtains the function for example, by calculatingan unfixed coefficient by the least squares method, and the function isstored in the storage device as correction information.

Here, it is all right to consider that the measurement error of eachencoder when substrate holder 32 is at Z position z in the case both thepitching amount and the yawing amount of substrate holder 32 are notzero, is a simple sum (linear sum) of the measurement errorcorresponding to the pitching amount and the measurement errorcorresponding to the yawing amount described above when at Z position z.

In the description below, for the sake of simplicity, for X heads (heads74 a, 74 d) of each X encoder, functions of pitching amount θy, yawingamount θz, and Z position z of the substrate holder are to be obtained,as is shown in the following formula (4) expressing measurement errorΔx, and are to be stored in the storage device. Also, for the Y heads(heads 74 b, 74 c) of each Y encoder, functions of rolling amount θx,yawing amount θz, and Z position z of substrate holder 32 are to beobtained, as is shown in the following formula (5) expressingmeasurement error Δy, and are to be stored in the storage device.

Δx=f(z, θy, θz)=θy(z−a)+θz(z−b)   (4)

Δy=g(z, θx, θz)=θx(z−c)+θz(z−d)   (5)

In formula (4) described above, a is a Z coordinate of an intersectingpoint of each of the straight lines that are plot points connected whenthe pitching amount is the same in the graph of FIG. 77 showing the casewhen the pitching amount is changed to acquire correction information onthe X encoder, and b is a Z coordinate of an intersecting point of eachof the straight lines that are plot points connected when the yawingamount is the same in a graph similar to the one in FIG. 77 when theyawing amount is changed to acquire correction information on the Xencoder. Also, in formula (5) described above, c is a Z coordinate of anintersecting point of each of the straight lines that are plot pointsconnected when the rolling amount is the same in a graph similar to theone in FIG. 77 showing the case when the rolling amount is changed toacquire correction information on the Y encoder, and d is a Z coordinateof an intersecting point of each of the straight lines that are plotpoints connected when the yawing amount is the same of a graph similarto the one in FIG. 77 when the yawing amount is changed to acquirecorrection information on the Y encoder.

Note that since Δx and Δy described above show the degree of influencethat the position of substrate holder 32 in the non-measurementdirection (e.g., θy direction or θx direction, θz direction, and Z-axisdirection) of the X encoder or the Y encoder has on the measurementvalues of the X encoder or the Y encoder, in the description, this willbe called error caused by holder position, and since this error causedby holder position can be used without any changes as correctioninformation, this correction information will be referred to ascorrection information on error caused by holder position.

Error Caused by Heads

As error caused by heads, measurement error of the encoder due to tiltof head can be given representatively. That is, when an optical axis ofa head is tilted with respect to a line perpendicular to the surface ofsubstrate P (vertical axis) in the case substrate P is arranged parallelto the horizontal plane, this means no other than tilt of substrate Pwith respect to the horizontal plane, in the case the head is parallelto the vertical axis (when the optical axis is not tilted). Accordingly,measurement errors occur in encoder measurement values. And with encoderheads of a diffraction interference method, measurement values areobtained based on photo-electrically converted signals which areobtained by irradiating two measurement beams on one point on thesubstrate from two directions symmetrical to the optical axis, andmaking two return beams that return interfere with each other. On thisoperation, intensity I of the interference light is proportional to1+cos φ (φ refers to a phase difference between the two return beams).Also, with the encoder heads of a diffraction interference method,measurement errors are set to become zero in advance when twomeasurement beams return passing through symmetrical optical paths.Therefore, when the optical axis of the heads is tilted, the differencedoes not become zero in the optical path lengths of the two opticalbeams (accordingly, optical beam phase difference φ of the two returnbeams change). Also, in the case the optical paths lose the symmetrydescribed above, phase difference φ also changes. That is,characteristic information on the head unit that becomes the cause ofmeasurement error occurring in the encoder system includes not only thetilt of head but also its optical properties.

In the liquid crystal exposure apparatus according to the embodiment,since one of a pair of heads 74 a and 74 b, and a pair of heads 74 c and74 d are fixed to each of a pair of head bases 88, by measuring tiltamount of head base 88 in the θx direction and the θy direction with theinterferometer or other displacement sensors, the tilt of head can bemeasured.

However, in the liquid crystal exposure apparatus according to theembodiment, the following points should be considered.

Since a pair of heads 74 a and 74 b and a pair of heads 74 c and 74 dare fixed to each of a pair of head bases 88, when rotation error in theθz direction occurs in head bases 88, then θz rotation error occurs inheads 74 a to 74 d with respect to two-dimensional grating RG that theheads face. From this, as is obvious from formulas (4) and (5) describedearlier, measurement error occurs in heads 74 a to 74 d. Accordingly, θzrotation of head base 88 is preferably measured with the interferometeror other displacement sensors.

Error Caused by Not Meeting Abbe Conditions

Now, when there is an error (or a gap) in height (Z position) of eachscale grating surface (two-dimensional grating surface) on scale base 84and height of a reference surface including the exposure center (centerof the exposure area described earlier), a so-called Abbe error occursin measurement values of the encoder on rotation (pitching or rolling)around an axis (Y-axis or X-axis) parallel to the XY plane of substrateholder 32, therefore, this error needs to be corrected. Here, referencesurface is a surface serving as a reference for position control in theZ-axis direction of substrate holder 32 (a surface serving as areference for displacement in the Z-axis direction of substrate holder32), or a surface coinciding with substrate P in the exposure operationof substrate P, and in the embodiment, is to coincide with an imageplane of projection optical system 16.

For correcting the error described above, height difference (so-calledAbbe offset error) between the height of each scale 2072 surface(two-dimensional grating surface) and the reference surface has to beaccurately obtained. This is because correcting the Abbe error caused bythe Abbe error offset amount described above is necessary to accuratelycontrol the position of substrate holder 32 within the XY plane usingthe encoder system. Taking into consideration such point, in theembodiment, main controller 100 performs calibration to obtain the Abbeoffset amount in the following procedure, for example, at the start uptime of the exposure apparatus.

First of all, on starting this calibration processing, main controller100 moves substrate holder 32 so that one scale 2072 of the firstgrating group is positioned below head 74 a, and at the same time, onescale 2072 of the second grating group is positioned below head 74 d.For example, as is shown in FIG. 74A, scale 2072 b is to be positionedbelow head 74 a, and at the same time, scale 2072 e is to be positionedbelow head 74 d.

Next, main controller 100, based on measurement results of theinterferometer system described earlier, in the case displacement(pitching amount) Δθy in the θy direction with respect to the XY planeof substrate holder 32 is not zero, makes substrate holder 32 tiltaround an axis parallel to the Y-axis and passing through the exposurecenter so that the pitching amount Δθy becomes zero based on themeasurement results of the interferometer system. At this point, sincethe interferometer system has all necessary correction completed foreach interferometer (each measurement axis), such a pitching control ofsubstrate holder 32 can be performed.

Then, after such adjustment of the pitching amount of substrate holder32, main controller 100 acquires measurement values x_(b0) and x_(e0) oftwo X encoders structured by heads 74 a and 74 d, and scales 2072 b and2072 e that heads 74 a and 74 d face.

Next, main controller 100, based on the measurement results of theinterferometer system, tilts substrate holder 32 by an angle ϕ aroundthe axis parallel to the Y-axis and passing through the exposure center.Then, main controller 100 acquires measurement values of the two Xencoders, measurement values x_(b1) and x_(e1), described above.

Then, main controller 100, based on measurement values x_(b0) andx_(e0), and x_(b1) and x_(e1) of the two encoders acquired above andangle ϕ described above, calculates the so-called Abbe offset amounth_(b) and h_(e) of scales 2072 b and 2072 e. In this case, since ϕ is aminute angle, sin ϕ=ϕ, cos ϕ=1 are established.

h _(b)=(x _(b1) −x _(b0))/ϕ  (6)

h _(e)=(x _(e1) −x _(e0))/ϕ  (7)

Main controller 100, in a procedure similar to the description above,uses one scale 2072 of the first grating group and one scale 2072 of thesecond grating group almost facing the scale in the first grating groupin the Y-axis direction as a set, and acquires the Abbe offset amountalso for the remaining scales. Note that the one scale 2072 of the firstgrating group and the one scale 2072 of the second grating group do nothave to be used simultaneously to measure the Abbe offset amount, andthe Abbe offset amount may be measured separately for each scale 2072.

As it can be seen from formulas (6) and (7) described above, whenpitching amount of substrate holder 32 is ϕy, Abbe error Δx_(abb) ofeach X encoder that accompanies the pitching of substrate holder 32 canbe expressed in the following formula (8).

Δx _(abb) =h·ϕy   (8)

In formula (8), h is the Abbe offset amount of scale 2072 that the Xhead structuring the X encoder faces.

Similarly, when rolling amount of substrate holder 32 is ϕx, then Abbeerror Δy_(abb) of each Y encoder that accompanies the rolling ofsubstrate holder 32 can be expressed in the following formula (9).

Δy _(abb) =h·ϕx   (9)

In formula (9), h is the Abbe offset amount of scale 2072 that the Yhead structuring the Y encoder faces.

Main controller 100 stores the Abbe offset amount h obtained for eachscale 2072 in the manner described above in the storage device. Thisallows main controller 100, on actual position control of substrateholder 32 such as during lot processing, to move (control the positionof) substrate holder 32 with high precision in an arbitrary directionwithin the XY plane, while correcting the Abbe error included in theposition information on substrate holder 32 within the XY plane(movement plane) measured by the holder encoder system, that is,measurement error of each X encoder corresponding to the pitching amountof substrate holder 32 caused by Abbe offset amount h of scale 2072grating surface (two-dimensional grating RG surface) with respect to thereference surface described earlier, or measurement error of each Yencoder corresponding to the rolling amount of substrate holder 32caused by Abbe offset amount h of scale 2072 grating surface(two-dimensional grating RG surface) with respect to the referencesurface described earlier, based on formula (8) or formula (9).

Note that, for example, since there are similar error factors also in anencoder system other than the holder encoder system (e.g., an encodersystem for measuring position of the coarse movement stage), correctioninformation on measurement errors should be acquired similarly, and themeasurement errors maybe corrected. This allows position information onthe holder (position information with the optical surface plate(projection optical system) serving as a reference) to be obtained withhigher precision, and further allows position controllability of theholder to be improved.

In the second embodiment, on actual position control of substrate holder32 such as during lot processing, main controller 100, while performingswitching of heads 74 a to 74 d of the holder encoder system with thechange of position in the X-axis direction of substrate holder 32,controls substrate drive system 60, based on correction information (tobe called a first correction information for convenience) to compensatefor measurement errors of the substrate measurement system caused by themovement of at least one of heads 74 a to 74 d, at least two scales thatthree heads of the heads 74 a to 74 d face, and substrate holder 32, andposition information measured by the substrate measurement system.

Here, the position information measured with the substrate measurementsystem includes measurement information on position (Z, θx, θy) of finemovement stage 32 by Z-tilt position measurement system 98 andmeasurement information on position (X, Y, θz) of substrate holder 32 bythe holder encoder system. The first correction information includescorrection information on various measurement errors (errors caused byscales, measurement errors (errors caused by holder position) caused byrelative movement between the heads and the scales in thenon-measurement direction, errors caused by heads, and Abbe errors) ofthe holder encoder system described earlier.

Accordingly, for example, at the time of exposure of substrate P,measurement values C₁ and C₄ of X encoder (heads 74 a and 74 d)measuring the X position of substrate holder 32 that have beencorrected, based on position information (including tilt information,such as, for example rotation information in the θy direction) ofsubstrate holder 32 in a direction different from the X-axis direction,characteristic information (for example, degree of flatness and/orgrating formation error of the grating surface of two-dimensionalgrating RG) of scale 2072 that the X head faces, and correctioninformation on Abbe error caused by Abbe offset amount of scale 2072(grating surface of two-dimensional grating RG), are used to calculatethe position coordinate (X, Y, θz) of substrate holder 32 describedearlier. More specifically, main controller 100 corrects measurementvalues of the X encoder (heads 74 a and 74 d) measuring positioninformation on substrate holder 32 in the X-axis direction, based oncorrection information (correction information calculated using formula(4) described earlier) of error caused by holder position correspondingto position information on substrate holder 32 in a direction(non-measurement direction) different from the X-axis direction, suchas, for example, position information in the θy direction, the θzdirection, and the Z-axis direction of substrate holder 32 measured byZ-tilt position measurement system 98, correction information on thegrating pitch of the X diffraction grating of two-dimensional grating RG(correction information taking into consideration the unevenness (degreeof flatness) of the scale grating surface (surface of two-dimensionalgrating RG)), correction information on grid line curve (errors at thetime of formation and temporal change) of the X diffraction grating oftwo-dimensional grating RG, and correction information on Abbe errorcaused by the Abbe offset amount of scale 2072 (grating surface oftwo-dimensional grating RG), and measurement values C₁ and C₄ aftercorrection are used to calculate the position coordinate (X, Y, θz) ofsubstrate holder 32 described earlier.

Similarly, measurement values C₂ and C₃ of Y encoder (heads 74 b and 74c) measuring the Y position of substrate holder 32 that have beencorrected, based on position information (including tilt information,such as, for example rotation information in the θx direction) ofsubstrate holder 32 in a direction different from the Y-axis direction,characteristic information (for example, degree of flatness and/orgrating formation error of the grating surface of two-dimensionalgrating RG) of scale 2072 that the Y head faces, and correctioninformation on Abbe error caused by Abbe offset amount of scale 2072(grating surface of two-dimensional grating RG), are used to calculatethe position coordinate (X, Y, θz) of substrate holder 32 describedearlier. More specifically, main controller 100 corrects measurementvalues of the Y encoder (heads 74 b and 74 c) measuring positioninformation on substrate holder 32 in the Y-axis direction, based oncorrection information (correction information calculated using formula(5) described earlier) of error caused by holder position correspondingto position information on substrate holder 32 in a direction(non-measurement direction) different from the Y-axis direction, suchas, for example, position information in the θx direction, the θzdirection, and the Z-axis direction of substrate holder 32 measured byZ-tilt position measurement system 98, correction information on thegrating pitch of the Y diffraction grating of two-dimensional grating RG(correction information taking into consideration the unevenness (degreeof flatness) of the scale grating surface (surface of two-dimensionalgrating RG)), correction information on grid line curve (errors at thetime of formation and temporal change) of the Y diffraction grating oftwo-dimensional grating RG, and correction information on Abbe errorcaused by the Abbe offset amount of scale 2072 (grating surface oftwo-dimensional grating RG), and measurement values C₂ and C₃ aftercorrection are used to calculate the position coordinate (X, Y, θz) ofsubstrate holder 32 described earlier.

Accordingly, in the embodiment, movement of substrate holder 32 iscontrolled, while position coordinates (X, Y, θz) of substrate holder 32is being calculated using three measurement values of the measurementvalues of X encoder (heads 74 a and 74 d) after correction and themeasurement values of Y encoder (heads 74 b and 74 c) after correctiondescribed above. This allows substrate holder 32 to be moved (positioncontrol) to compensate for all errors described earlier; error caused byscales, error caused by holder position, error caused by heads, and Abbeerror, of the three encoders consisting of three heads (three out ofheads 74 a to 74 d) used for position control of the substrate holderand scales 2072 facing the heads.

However, in the case the encoder (head) used after the switchingdescribed earlier is head 74 c, on obtaining the initial value of themeasurement values of head 74 c, because C₃ obtained from the affinetransformation formula (3) described earlier is a corrected measurementvalue of the encoder whose various measurement errors described earlierhave been corrected, main controller 100, using correction informationon error caused by holder position, correction information on thegrating pitch of the scale (and correction information on gratingdeformation), Abbe offset amount (Abbe error correction information) andthe like described earlier, inversely corrects measurement value C₃, andcalculates raw value C₃′ before correction, and obtains raw value C₃′ asthe initial value of the measurement values of the encoder (head 74 c).

Here, inverse correction refers to a processing of calculatingmeasurement value C₃′ being a measurement value without any correctionbased on measurement value C₃, under the assumption that the measurementvalue of the encoder after correction is C₃ that has been correctedusing correction information on error caused by holder position,correction information on error caused by scales (e.g. correctioninformation on grating pitch of the scale (and correction information ongrating deformation) and the like), Abbe offset amount (Abbe errorcorrection information) and the like described earlier.

The liquid crystal exposure apparatus according to the twentiethembodiment described so far has a working effect equivalent to the firstembodiment described earlier. Adding to this, with the liquid crystalexposure apparatus according to the twentieth embodiment, whilesubstrate holder 32 is moved, position information (including θzrotation) on substrate holder 32 within the XY plane is measured bythree heads (encoders) including at least one each of X head 74 x (Xlinear encoder) and Y head 74 y (Y linear encoder) of substratemeasurement system 2070. Then, by main controller 100, the head(encoder) used for measuring position information on substrate holder 32within the XY plane is switched from one of the heads (encoders) of thethree heads used for measuring the position and position control ofsubstrate holder 32 before switching to another head (encoder), so thatthe position of substrate holder 32 within the XY plane is maintainedbefore and after the switching. Therefore, the position of substrateholder 32 within the XY plane is maintained before and after theswitching and an accurate linkage becomes possible, even thoughswitching of the encoders used for controlling the position of substrateholder 32 has been performed. Accordingly, it becomes possible to movesubstrate holder 32 (substrate P) along the XY plane accurately along apredetermined moving route, while performing switching and linkage(linkage process of measurement values) of heads among a plurality ofheads (encoders).

Also, with the liquid crystal exposure apparatus according to thetwentieth embodiment, for example, during exposure of the substrate,substrate holder 32 is moved within the XY plane by main controller 100,based on measurement results of position information on substrate holder32 and position information ((X, Y) coordinate values) within the XYplane of the three heads used for measuring the position information. Inthis case, main controller 100 moves substrate holder 32 within the XYplane while calculating the position information on substrate holder 32within the XY plane using the affine transformation relation. Thisallows the movement of substrate holder 32 (substrate P) to becontrolled with good accuracy, while switching the heads (encoders) usedfor control during the movement of substrate holder 32 using encodersystems having each of a plurality of Y heads 74 y or a plurality of Xheads 74 x.

Also, with the liquid crystal exposure apparatus according to thetwentieth embodiment, offsets ΔX, ΔY, Δθz (grating correctioninformation) described earlier are acquired and are updated asnecessary, for each combination of scales that the heads used forposition measurement and position control of substrate holder 32 faceand are different depending on the X position of substrate holder 32.

Accordingly, it becomes possible to move (perform position control of)substrate holder 32 so that the measurement error of the encoder due togrid error (X, Y position errors and rotation error) between coordinatesystems for each combination of scales that the heads used for positionmeasurement and position control of substrate holder 32 face and aredifferent depending on the X position of substrate holder 32 or positionerror of substrate holder 32 are compensated. Accordingly, on this pointas well, the position of the substrate holder (substrate P) can becontrolled with good accuracy.

Also, with the liquid crystal exposure apparatus according to the secondembodiment, on actual position control of substrate holder 32 such asduring lot processing, controls substrate drive system 60, based oncorrection information (the first correction information describedearlier) to compensate for measurement errors of the substratemeasurement system caused by the movement of at least one of heads 74 ato 74 d of the holder encoder system, at least two scales that threeheads of the heads 74 a to 74 d face, and substrate holder 32, andposition information measured by the substrate measurement system.Accordingly, substrate holder 32 can be moved and controlled tocompensate for various measurement errors described earlier of each Xencoder and Y encoder structuring the holder encoder system. On thispoint as well, position control of the substrate holder (substrate P)can be performed with good accuracy.

Also, in the twentieth embodiment described above, the first correctioninformation was to include all of correction information (correctioninformation on error caused by heads) to compensate for measurementerrors of the substrate measurement system caused by heads 74 a to 74 dof the holder encoder system, correction information (correctioninformation on error caused by scales) to compensate for measurementerrors (error caused by scales) caused by at least two scales that threeheads of the heads 74 a to 74 d face, and correction information tocompensate for measurement errors of the substrate position measurementsystem (error caused by holder position) caused by the movement ofsubstrate holder 32. However, the embodiment is not limited to this, andas for the holder encoder system, correction information to compensatefor at least one of the error caused by heads, error caused by scales,and error caused by holder position may be used. Note that the Abbeerror (error caused by not meeting Abbe conditions) is included in oneof, or both of the error caused by scales and error caused by holderposition. Also, while all of correction information on measurementerrors caused by unevenness of the scales, correction information ongrating pitch of the scales, and correction information on gratingdeformation was used as correction information on error caused by scalesto control the position of substrate holder 32, it is fine to use onlyat least one of the correction information on the these errors caused byscales. Similarly, while measurement errors caused by displacement ofheads (including tilt and rotation) and measurement errors caused byoptical properties were referred to as error caused by heads, it is fineto use only at least one of the correction information on these errorscaused by heads to control the position of substrate holder 32.

Also, similar to each encoder of the encoder system measuring theposition information on substrate holder 32, correction information onmeasurement errors of heads (encoders) caused by relative movementbetween each head and a scale that each head faces in a directiondifferent from the measurement direction of each encoder may be obtainedalso for each head (encoder) of the mask encoder system, similarly as isdescribed earlier, and the correction information may be used to correctthe measurement errors of the heads (encoders).

Note that with the liquid crystal exposure apparatus according to thetwentieth embodiment, an interferometer system similar to theinterferometer system used to acquire errors caused by scales (and thecorrection information) of the holder encoder system and the likeperformed at the time of maintenance described earlier may be arrangedin the apparatus. In such a case, correction information and the like oferrors caused by scales of the holder encoder system can be acquired andupdated appropriately, not only at the time of maintenance but alsoduring the operation of the apparatus. Also, while another measurementdevice (such as an interferometer) was used to acquire the correctioninformation described above, the correction information may be acquiredsimilarly by using the encoder system, or through the exposureprocessing using a wafer for measurement, without using the anothermeasurement device.

Note that in the twentieth embodiment described above, while thecorrection information (initial value of the another head previouslydescribed) for controlling the movement of the substrate holder wasacquired using the head (corresponding to the another head describedabove) whose measurement beam moves off from one of the adjacent pair ofscales and switches to the other scale, based on the positioninformation measured by the three heads facing at least one scale 2072,this correction information should be acquired after the measurementbeam of the another head is switched to the other scale, by the time oneof the three heads facing at least one scale 2072 moves off fromtwo-dimensional grating RG. Also, in the case of performing positionmeasurement or position control of the substrate holder by switching thethree heads facing at least one scale 2072 to three different headsincluding the another head described above, this switching should beperformed after the correction information described above has beenacquired, by the time one of the three heads facing at least one scale2072 moves off from two-dimensional grating RG. Note that acquiring thecorrection information and the switching may substantially be performedat the same time.

Note that in the twentieth embodiment described above, each of the fivescales 2052 of the first grating group and the second grating group isarranged on substrate holder 32 so that the area that has notwo-dimensional grating RG of the first grating group (non-grating area)does not overlap the area that has no two-dimensional grating RG of thesecond grating group (non-grating area) in the X-axis direction (firstdirection), or in other words, so that the non-measurement period inwhich the measurement beam moves off from two-dimensional grating RGdoes not overlap in the four heads. In this case, heads 74 a and 74 bthat head base 88 on the +Y side has, are arranged at a spacing widerthan the width of the area that has no two-dimensional grating RG of thefirst group in the X-axis direction, and heads 74 c and 74 d that headbase 88 on the −Y side has, are arranged at a spacing wider than thewidth of the area that has no two-dimensional grating RG of the secondgroup in the X-axis direction. However, the combination of the gratingsection including the plurality of two-dimensional gratings and theplurality of heads that can face the grating section is not limited tothis. The point is, spacing between heads 74 a and 74 b and spacingbetween heads 74 c and 74 d, position, position and length of thegrating section of the first and second grating groups or spacingbetween the grating sections and their position should be set, so thatthe (non-measurable) non-measurement period in which the measurementbeam moves off from two-dimensional grating RG does not overlap in thefour heads 74 a, 74 b, 74 c, and 74 d during the movement of the movablebody in the X-axis direction. For example, even if the position and thewidth of the non-grating area in the X-axis direction is the same in thefirst grating group and the second grating group, two heads facing atleast one scale 2072 (two-dimensional grating RG) of the first gratinggroup and two heads facing at least one scale 2072 (two-dimensionalgrating RG) of the second grating group may be arranged shifted only bya distance wider than the width of the non-grating area in the X-axisdirection. In this case, the spacing between the head arranged on the +Xside of the two heads facing the first grating group and the headarranged on the −X side of the two heads facing the second grating groupmay be set wider than the width of the non-grating area, or the twoheads facing the first grating and the two heads facing the secondgrating may be arranged alternately in the X-axis direction with thespacing between adjacent pair of heads may be set wider than the widthof the non-grating area.

Also, in the twentieth embodiment described above, while the case hasbeen described in which the first grating group is arranged in an areaon the +Y side of substrate holder 32, and the second grating group isarranged in an area on the −Y side of substrate holder 32, instead ofone of the first grating group and the second grating group, such asinstead of the first grating group, a single scale member on which atwo-dimensional grating extending in the X-axis direction is formed maybe used. In this case, one head may be made to constantly face thesingle scale member. In this case, a structure may be employed in whichthree heads may be provided to face the second grating group, and bymaking the spacing (spacing between irradiation positions of themeasurement beams) in the X-axis direction of the three heads wider thanthe spacing between two-dimensional grating RG on adjacent scales 2072,at least two of the three heads facing the second grating group can faceat least one two-dimensional grating RG of the second grating groupregardless of the position of substrate holder 32 in the X-axisdirection. Or, a structure may be employed in which at least two headsconstantly face the single scale member described above regardless ofthe position of substrate holder 32 in the X-axis direction, togetherwith at least two heads facing at least one two-dimensional grating RGof the second grating group. In this case, each of the measurement beamsof the at least two heads moves off from one of the plurality of scales2072 (two-dimensional grating RG) during the movement of substrateholder 32 in the X-axis direction, and is switched to another scale 2072(two-dimensional grating RG) adjacent to the one scale 2072(two-dimensional grating RG). However, by making the spacing between theat least two heads in the X-axis direction wider than the spacing oftwo-dimensional grating RG of adjacent scales 2072, the non-measurementperiod does not overlap in the at least two heads, that is, themeasurement beam of at least one head constantly irradiates scale 2072.In these structures, at least three heads constantly face at least onescale 2072, allowing position information to be measured in directionsof three degrees of freedom.

Note that the number of scales, spacing between adjacent scales and thelike may be different in the first grating group and the second gratinggroup. In this case, in at least two heads facing the first gratinggroup and at least two heads facing the second grating group, spacingbetween the heads (measurement beams), position and the like may bedifferent.

Note that in the second embodiment described above, while the pluralityof scales 2072 having a single two-dimensional grating RG (grating area)formed on each scale was used, the present invention is not limited tothis, and at least one of the first grating group or the second gratinggroup may include a scale 2072 that has two or more grating areas formedapart in the X-axis direction.

Note that in the twentieth embodiment described above, while the casehas been described in which to measure and control the positions (X, Y,θz) of substrate holder 32 constantly by three heads, the first gratinggroup and the second grating group including five scales 2072 eachhaving the same structure are arranged shifted by a predetermineddistance in the X-axis direction, the embodiment is not limited to this,and the heads (heads 74 x, 74 y) for position measurement of substrateholder 32 may be arranged differently in the X-axis direction in one ofthe head bases 88 and the other of the head bases 88, without the firstgrating group and the second grating group being shifted in the X-axisdirection (arrange rows of scales 2072 to almost completely face eachother). Also in this case, the position (X, Y, θz) of substrate holder32 can constantly be measured and controlled by the three heads.

Note that in the twentieth embodiment described above, while the case ofusing a total of four heads, heads 74 a and 74 b and heads 74 c and 74 dhas been described, the embodiment is not limited to this, and five ormore heads may also be used. That is, to one of the two heads eachfacing the first grating group and the second grating group, at leastone of redundant head may be added. This structure will be described ina twenty-first embodiment below.

Twenty-first Embodiment

Next, a twenty-first embodiment will be described, based on FIG. 75.Since the structure of the liquid crystal exposure apparatus accordingto the twenty-first embodiment is the same as the first and thetwentieth embodiments previously described except for the structure of apart of a substrate measurement system 2170, only the different pointswill be described below, and for elements having the same structure andfunction as the first and the twentieth embodiments will have the samereference code as the first and the twentieth embodiments, and thedescription thereabout will be omitted.

FIG. 21 shows substrate holder 32 and the pair of head bases 88 ofsubstrate measurement system 2170 according to the twentieth embodimentin a planar view, along with projection optical system 16. In FIG. 75,to make the description comprehensive, illustration of Y coarse movementstage 24 and the like is omitted. Also, in FIG. 75, head bases 88 areillustrated in a dotted line, while illustration of X heads 80 x and Yheads 80 y provided on the upper surface of head bases 88 are omitted.

With the liquid crystal exposure apparatus according to the twenty-firstembodiment, as is shown in FIG. 75, in each of the areas on the +Y sideand the −Y side of substrate holder 32 with the substrate mounting areain between, for example, five scales 2072 are arranged at apredetermined spacing in the X-axis direction. With the five scales 2072arranged on the +Y side of the substrate mounting area and the fivescales 2072 arranged on the −Y side, the spacing between adjacent scales2072 is the same, and the five scales 2072 on the +Y side of thesubstrate mounting area and the five scales 2072 on the −Y side arearranged at the same X position, facing each other. Accordingly, theposition of the spacing between adjacent scales 2072 is located onalmost the same straight line in the Y-axis direction that has apredetermined width.

To the lower surface (surface on the −Z side) of one of the head bases88 positioned on the +Y side, a total of three heads, Y head 74 y, Xhead 74 x, and Y head 77 y are fixed apart by a predetermined spacing (adistance larger than the spacing between adjacent scales 2072) in theX-axis direction from the −X side, in a state each facing scale 2072. Tothe lower surface (surface on the −Z side) of the other head base 88positioned on the −Y side, Y head 74 y and X head 74 x are fixed setapart by a predetermined spacing in the X-axis direction, in a stateeach facing scale 2072. In the description below, for convenience ofexplanation, three heads that one of the head bases 88 has will bereferred to as head 74 e, head 74 a, and head 74 b from the −X side, andY head 74 y and X head 74 x that the other head base 88 has will bereferred to as head 74 c and head 74 d, respectively.

In this case, head 74 a and head 74 c are arranged at the same Xposition (on the same straight line in the Y-axis direction), and head74 b and head 74 d are arranged at the same X position (on the samestraight line in the Y-axis direction). Heads 74 a and 74 d and thetwo-dimensional gratings RG that face each head structure a pair of Xlinear encoders, and heads 74 b, 74 c, and 74 e and the two-dimensionalgratings RG that face each head structure three Y linear encoders.

With the liquid crystal exposure apparatus according to the twenty-firstembodiment, the structure of other parts is similar to the liquidcrystal exposure apparatus according to the twentieth embodimentdescribed earlier.

In the twenty-first embodiment, although the arrangement of the row ofscales 2072 on the +Y side and the −Y side is not shifted in the X-axisdirection, as long as the pair of head bases 88 moves (or the Y positionof substrate holder 32 is maintained at a position where the pair ofhead bases 88 faces the row of scales 2072) in the Y-axis directionsynchronously with substrate holder 32, three heads of heads 74 a to 74e constantly faces scale 2072 (two-dimensional grating RG) regardless ofthe X position of substrate holder 32.

The liquid crystal exposure apparatus according to the twenty-firstembodiment described so far has a working effect equivalent to thetwentieth embodiment described earlier.

Note that in the twenty-first embodiment described above, it can beregarded that in addition the four heads necessary for switching ofheads, e.g., heads 74 e, 74 b, 74 c, and 74 d, the plurality of headsfor measuring position information on substrate holder 32 includes onehead 74 a whose non-measurement period partly overlaps one head 74 c ofthe four heads. And, in the twenty-first embodiment, on measuringposition information (X, Y, θz) of substrate holder 32, of the fiveheads including the four heads 74 e, 74 b, 74 c, and 74 d and the onehead 74 c, measurement information on at least three heads is used thatirradiate at least one of the plurality of grating areas(two-dimensional gratings RG) with a measurement beam.

Note that the twenty-first embodiment described above is an example of acase when the non-measurement period overlaps in at least two heads of aplurality of heads, such as, for example, when two heads move off fromscale 2072 (grating area, e.g. two-dimensional grating RG) at the sametime, and simultaneously switch to an adjacent scale 2072 (grating area,e.g. two-dimensional grating RG). In this case, to continue measurementeven if the measurement is cut off for the at least two heads, at leastthree heads need to face the grating area (two-dimensional grating) ofthe grating section. Moreover, as a premise, the measurement should notbe cut off for the at least three heads until one or more of the atleast two heads whose measurement has been cut off switches to anadjacent grating area. That is, even if there is at least two headswhose non-measurement period overlaps, if there is at least three headsadding to the at least two heads, measurement can be continued even ifthe grating areas are arranged spaced apart.

Twenty-second Embodiment

Next, a twenty-second embodiment will be described, based on FIG. 76.While the structure of the liquid crystal exposure apparatus accordingto the twenty-second embodiment, as is shown in FIG. 76, is differentfrom the structure of the liquid crystal exposure apparatus according tothe twenty-first embodiment described earlier on the points that the rowof scales 2072 arranged at both the +Y side and the −Y side of thesubstrate mounting area of substrate holder 32 are arranged facing eachother similarly as in the twenty-first embodiment, and that one of thehead bases 88 positioned on the −Y side has two each of X heads 74 x andY heads 74 y similarly to the twentieth embodiment, the structure ofother parts is similar to the liquid crystal exposure apparatusaccording to the twenty-first embodiment.

To the lower surface (surface on the −Z side) of Y one of the head bases88, X head 74 x (hereinafter appropriately called head 74 e) is providedarranged adjacent to Y head 74 y (head 74 c) on the −Y side, along withY head 74 y (hereinafter appropriately called head 74 f) providedarranged adjacent to X head 74 x (head 74 d) on the −Y side.

With the liquid crystal exposure apparatus according to the embodiment,in a state when the pair of head bases 88 is moving in the Y-axisdirection (or when the Y position of substrate holder 32 is maintainedat a position where the pair of head bases 88 face the row of scales2072), a case may occur when one of three heads 74 a, 74 c, and 74 e (tobe referred to as heads of a first group) and three heads 74 b, 74 d,and 74 f (to be referred to as heads of a second group) do not face anyof the scales due to substrate holder 32 moving in the X-axis direction,and when this occurs, the other of the heads of the first group and theheads of the second group face scale 2072 (two-dimensional grating RG)without fail. That is, in the liquid crystal exposure apparatusaccording to the twenty-second embodiment, although the arrangement ofscales 2072 lined on the +Y side and the −Y side is not shifted in theX-axis direction, as long as the pair of head bases 88 moves (or the Yposition of substrate holder 32 is maintained at a position where thepair of head bases 88 faces the row of scales 2072) in the Y-axisdirection, the positions (X, Y, θz) of substrate holder 32 can bemeasured regardless of the X position of substrate holder 32, by thethree heads included in at least one of the heads of the first group andthe heads of the second group.

Here, a case will be considered, for example, of restoring (re-startmeasurement of) the heads of the first group (heads 74 a, 74 c, and 74e) when the heads face scale 2072 again, after heads 74 a, 74 c, and 74e no longer face any of the scales and have become non-measurable. Inthis case, at the point before measurement is re-started by the heads ofthe first group (heads 74 a, 74 c, and 74 e), the positions (X, Y, θz)of substrate holder 32 is being continuously measured and controlled bythe heads of the second group (heads 74 b, 74 d, and 74 f). Therefore,main controller 100, as is shown in FIG. 76, at the point when the pairof head bases 88 crosses over adjacent two scales 2072 arranged on eachof the +Y side and the −Y side and the heads of the first group and theheads of the second group face one and the other of the adjacent twoscales 2072, respectively, calculates the positions (X, Y, θz) ofsubstrate holder 32 by the method described in detail in thetwenty-first embodiment based on measurement values of the heads of thesecond group (heads 74 b, 74 d, and 74 f), and by substituting thepositions (X, Y, θz) of the substrate holder into the formula of affinetransformation described earlier, initial values of the heads of thefirst group (heads 74 a, 74 c, and 74 e) are calculated and set at thesame time. This allows the heads of the first group to be restored andto re-start measurement and control of the position of substrate holder32 with these heads easily.

With the liquid crystal exposure apparatus according to thetwenty-second embodiment described so far, the apparatus exhibits aworking effect equivalent to the twenty-first embodiment describedearlier.

Modified Example of the Twenty-second Embodiment

This modified example describes a case when a head unit having anidentical structure (or a structure symmetrical in the verticaldirection of the page surface) as one of the head bases 88 is used asthe other head base 88 positioned on the +Y side, in the liquid crystalexposure apparatus according to the twenty-second embodiment.

In this case, similarly to the description above, eight heads aregrouped into four heads each being arranged on the same straight line inthe Y-axis direction; heads of a first group, and heads of a secondgroup.

A case will be considered of restoring the heads of a first group andre-start measurement with these heads when the heads face scales 2072again, after the heads of the first group no longer face any of thescales and can no longer perform measurement.

In this case, at the point before measurement is re-started by the headsof the first group, the positions (X, Y, θz) of substrate holder 32 isbeing continuously measured and controlled by three heads of the headsof the second group. Therefore, main controller 100, as is describedearlier, at the point when the pair of head bases 88 crosses overadjacent two scales 2072 arranged on each of the +Y side and the −Y sideand the heads of the first group and the heads of the second group faceone and the other of the adjacent two scales 2072, respectively,calculates initial values of each of the heads of the first group;however, in this case, the main controller cannot calculate the initialvalues of all four heads of the first group at the same time. This isbecause if the heads to be restored for measurement were three (thenumber of X heads and Y heads added), when the initial values of themeasurement values of the three heads are set in the procedure describedearlier, by solving the simultaneous equations described earlier usingthe initial values as measurement values C₁, C₂, C₃ and the like, thepositions (X, Y, θz) of the substrate holder is uniquely decided, whichcauses no problems in particular. However, simultaneous equations usingthe affine transformation relation that can uniquely decide thepositions (X, Y, θz) of the substrate holder using measurement values offour heads cannot be conceived.

Therefore, in the modified example, the first group to be restored is tobe grouped into two groups; each having three heads including differentheads, and the initial values are calculated and set simultaneously forthe three heads for each group in the method described earlier. Afterthe initial values have been set, the measurement values of either ofthe groups may be used for position control of substrate holder 32.Position measurement of substrate holder 32 by the heads of the groupnot used for position control may be executed in parallel with positioncontrol of substrate holder 32. Note that the initial values of eachhead of the first group to be restored can be sequentially calculatedindividually, by the method described earlier.

Switching process of encoders (linkage of encoder output) according tothe twentieth to the twenty-second embodiments described above can alsobe applied to the encoder systems in the second to nineteenthembodiments which perform position measurement of a substrate holderwith the coarse movement stage or the measurement table serving as areference. Also, the switching process of encoders (linkage of encoderoutput) according to the twentieth to the twenty-second embodimentsdescribed above can also be applied to the encoder system in each of thefirst to the fifth, the eighth to the fifteenth, the eighteenth, and thenineteenth embodiments which performs position measurement of the coarsemovement stage with optical surface plate 18 a serving as a reference,or also to the encoder system in each of the sixth, the seventh, thesixteenth, and the seventeenth embodiments which performs positionmeasurement of the measurement table with optical surface plate 18 aserving as a reference.

Note that the structures described so far in the first to thetwenty-second embodiments can be changed as appropriate. As an example,the substrate measurement system (substrate measurement system 70, 270and the like) in each of the embodiments described above can be used forposition measurement of a movable body holding an object (substrate P ineach of the embodiments described above), regardless of the structure ofthe substrate stage device. That is, to a substrate stage deviceequipped with a substrate holder which is a type that holds almost theentire surface of substrate P by suction such as substrate holder 32according to the first to fifth embodiments described above, it ispossible to apply a measurement system like substrate measurement system670 according to the sixth embodiment described above which is a type ofsystem that obtains position information on the substrate holder viameasurement table 624 with optical surface plate 18 a serving as areference.

Also, a measurement system similar to the measurement system accordingto each of the embodiments described above may be used for measurementtargets other than substrate P, and as an example, a measurement systemhaving a structure similar to substrate measurement system 70 or thelike described above may be used for measurement the position of mask Min mask stage device 14. Especially to a measurement system of a maskstage device that steps the mask in long strokes in a directionorthogonal to the scanning direction of the mask as is described in,International Publication WO2010/131485, the measurement systemaccording to each of the embodiments described above may be suitablyapplied.

Also, in the substrate measurement system of the first to thetwenty-second embodiments, the arrangement of encoder heads and scalesmay be reversed. That is, X linear encoders and Y linear encoders forobtaining position information on the substrate holder may have scalesattached to the substrate holder, and encoder heads attached to thecoarse movement stage or to the measurement table. In this case, thescale attached to the coarse movement stage or the measurement table maybe arranged, for example, along the X-axis direction in a plurality ofnumbers, and are preferably structured switchable with one another.Similarly, X linear encoders and Y linear encoders for obtainingposition information on the coarse movement stage or the measurementtable may have scales attached to the measurement table and encoderheads attached to optical surface plate 18 a. In this case, the encoderhead attached to optical surface plate 18 a may be arranged, forexample, along the Y-axis direction in a plurality of numbers, and arepreferably structured switchable with one another. In the case theencoder heads are fixed to the substrate holder and optical surfaceplate 18, the scales fixed to the coarse movement stage or themeasurement table may be shared.

Also, in the substrate measurement system, while the case has beendescribed where one or a plurality of scales are fixed extending in theX-axis direction on the substrate stage device side and one or aplurality of scales are fixed extending in the Y-axis direction on theapparatus main section 18 side, the substrate measurement system is notlimited to this, and one or a plurality of scales extending in theY-axis direction may be fixed on the substrate stage device side and oneor a plurality of scales extending in the X-axis direction may be fixedon the apparatus main section 18 side. In this case, the coarse movementstage or the measurement table is moved in the X-axis direction whilethe substrate holder is being moved in exposure operation and the likeof substrate P.

Also, in the case a plurality of scales is arranged separately, thenumber of scales is not limited in particular and can be appropriatelychanged, for example, according to the size of substrate P or themovement strokes of substrate P. Also, a plurality of scales havingdifferent lengths may be used, and the number of scales structuring thegrating section does not matter, as long as each of the grating sectionsincludes a plurality of grating areas arranged side by side in theX-axis direction or the Y-axis direction.

Also, although the structure is employed in which the measurement tableand its driver are provided at the lower surface of upper mount section18 a of apparatus main section 18, the measurement table and its drivermay be provided at lower mount section 18 b or at middle mount section18 c.

Also, in each of the embodiments described above, while the case hasbeen described where a scale on which a two-dimensional grating isformed is used, however, the embodiments are not limited to this, and anX scale and a Y scale maybe formed independently on the surface of eachscale. In this case, within the scale, the length of the X scale and theY scale may be made different. Also, the X scale and the Y scale may bearranged relatively shifted in the X-axis direction. Also, while thecase of using a diffraction interference encoder system has beendescribed, the encoder is not limited to this, and other encoders suchas the so-called pick-up system or a magnetic system may also be used,and the so-called scan encoder whose details are disclosed in, forexample, U.S. Pat. No. 6,639,686 may also be used.

Note that in the twentieth to the twenty-second embodiments and themodified example (hereinafter shortly referred to as the twenty-secondembodiment) described above, while the case has been described in whichat least four heads are provided, in such a case, the number of scales2072 structuring the grating section does not matter, as long as thegrating section includes a plurality of grating areas arranged side byside in the first direction. The plurality of grating areas does notnecessarily have to be arranged on both one side and the other side inthe Y-axis direction with substrate P of substrate holder 32 in between,and may be arranged only on one side. However, to continuously controlthe position (X, Y, θz) of substrate holder 32 at least during theexposure operation of substrate P, the following conditions need to besatisfied.

That is, while a measurement beam of one head of the at least four headsmove off from the plurality of grating areas (e.g., two-dimensionalgrating RG described earlier), along with at least the three headsremaining irradiate at least one of the plurality of grating areas withthe measurement beams, by movement of substrate holder 32 in the X-axisdirection (the first direction, the one head described above whosemeasurement beam moves off from the plurality of grating areas isswitched in the at least four heads described above. In this case, theat least four heads include; two heads whose positions (irradiationpositions) of the measurement beams in the X-axis direction (the firstdirection) are different from each other, and two heads whose positionsof the measurement beams in the Y-axis direction (the second direction)are different from at least one of the two heads along with positions(irradiation positions) of the measurement beams in the X-axis direction(the first direction) being different from each other, and the two headsirradiate measurement beams in the X-axis direction at a spacing widerthan the spacing of a pair of adjacent grating areas of the plurality ofgrating areas.

Note that the grating areas (e.g. two-dimensional grating RG) arrangedside by side in the X-axis direction may be arranged in the Y-axisdirection in three or more rows. For example, in the twenty-secondembodiment described above, instead of the five scales 2072 on the −Yside, a structure may be employed in which two rows of grating areas(e.g. two-dimensional gratings RG) adjacent in the Y-axis direction areprovided, consisting of 10 grating areas (e.g. two-dimensional gratingsRG) having an area which is half of each of the five scales 2072 in theY-axis direction, and heads 74 e and 74 f can be made to facetwo-dimensional grating RG, at one of the rows and heads 74 c and 74 dcan be made to face two-dimensional grating RG at the other of the rows.Also, in the modified example of the twentieth embodiment describedabove, also for the five scales 2072 on the +Y side, a structure may beemployed in which two rows of grating areas (e.g.

two-dimensional gratings RG) adjacent in the Y-axis direction areprovided, consisting of 10 grating areas similar to the descriptionabove, and a pair of heads can be made to face two-dimensional gratingRG at one of the rows, and the remaining pair of heads can be made toface two-dimensional grating RG at the other of the rows.

Note that in the twentieth to the twenty-second embodiments describedabove, it is important to set position or spacing, or position andspacing and the like of at least one of scales and heads, so that atleast among the mutual four heads, measurement beams not beingirradiated on (move off from the grating areas of) any of thetwo-dimensional gratings RG, that is, measurement with the heads beingnon-measurable (non-measurement section) does not overlap for any twoheads, when substrate holder 32 moves in the X-axis direction (the firstdirection).

Note that from the twentieth to the twenty-second embodiment describedabove, while initial values of another head are to be set when ameasurement beam moves off from one scale and switches to another scale,the embodiments are not limited to this, and correction information tocontrol the movement of substrate holder may be acquired using anotherhead, such as correction information on measurement values of anotherhead. While the correction information to control the movement of thesubstrate holder using another head naturally includes initial values,the embodiments are not limited to this, and as long as the informationcan be used for the another head to re-start measurement, theinformation may be offset values from the values that should be measuredafter the measurement is re-started.

Note that from the twentieth to the twenty-second embodiment describedabove, instead of each X head 74 x measuring position information onsubstrate holder 32, an encoder head (XZ head) whose measurementdirection is in the X-axis direction and the Z-axis direction may beused, together with an encoder head (YZ head) whose measurementdirection is in the Y-axis direction and the Z-axis direction instead ofeach Y head 74 y. As these heads, a sensor head having a structuresimilar to the displacement measurement sensor head disclosed in, forexample, U.S. Pat. No. 7,561,280, can be used. In such a case, onswitching and linkage process of the heads described earlier, adding tothe linkage process performed to secure continuity of measurementresults of the position of substrate holder 32 in directions of threedegrees of freedom (X, Y, θz) in the XY plane by performing apredetermined calculation using measurement values of three heads usedfor position control of substrate holder 32 before switching, maincontroller 100 may also perform the linkage process to secure continuityof measurement results of the position of substrate holder 32 in theremaining directions of three degrees of freedom (Z, θx, θy) by asimilar method described earlier. Specifically, taking the twentiethembodiment representatively as an example, main controller 100 mayacquire correction information for controlling the movement of substrateholder 32 in the remaining directions of three degrees of freedom (Z,θx, θy) using one head whose measurement beam moves off from onetwo-dimensional grating RG (grating area) and switches to anothertwo-dimensional grating RG (grating area) of the four heads 74 a, 74 b,74 c, and 74 d, based on measurement information in the Z-axis direction(a third direction) by the remaining three heads or position informationon substrate holder 32 in the remaining directions of three degrees offreedom (Z, θx, θy) measured by the remaining three heads.

Also, when height and tilt of a plurality of scale plates 2072 aremutually shifted, displacement occurs between the coordinate systemsdescribed earlier, which causes measurement error in the encoder system.Therefore, the measurement error in the encoder system caused by theshift of height and tilt of the plurality of scale plates 2072 may becorrected. For example, as is described earlier, in the twentiethembodiment, on switching the heads, at the point when setting theinitial value of the head used after the switching, the fifth stateoccurs in which the four heads 74 a to 74 d all simultaneously faceeither one the scales 2072. Therefore, main controller 100, by using themeasurement values of the redundant head in this fifth state, mayperform calibration (calibration) of the displacement between thecoordinate systems caused by the displacement of height and tilt of theplurality of scale plates 2072.

For example, similarly to acquiring the offsets (ΔX, ΔY, Δθz) describedearlier, measurement can be performed of the position (Z, θx, θy) ofsubstrate holder 32 by two sets of the heads in a set of three in thefifth state and difference between the measurement values obtained bythe measurement, that is, offsets ΔZ, Δθx, and Δθy can be obtained, andthe offsets can be used for measuring position information on substrateholder 32 before and after switching of heads and for calibration ofdisplacement in the Z-axis direction, the θx direction, and the θydirection between coordinate systems each determined by the combinationof at least two scales facing the three heads used for position control.

Note that in the first to twenty-second embodiments, while the substratemeasurement system was structured by the Z-tilt position measurementsystem and the encoder system, for example, by using XZ and YZ headsinstead of X and Y heads, the substrate measurement may be structuredonly by the encoder system.

Also, in the seventeenth embodiment described above, other than the pairof measurement tables 1782, at least one head may be provided which isarranged away from measurement table 1782 in the X-axis direction. Forexample, movable head units which are the same as measurement tables1782 may be provided with respect to the +Y side and −Y side of a markdetection system (alignment system) which is arranged away fromprojection optical system 16 in the X-axis direction and detectsalignment marks on substrate P, and on detection operation of substratemarks, position information on Y coarse movement stage 24 maybe measuredusing the pair of head units arranged on the +Y side and the −Y side ofthe mark detection system. In this case, on the mark detectionoperation, even if all measurement beams move off from scales 1788 (or684) at the pair of measurement tables 1782, measurement of positioninformation on Y coarse movement stage 24 by the substrate measurementsystem (another pair of head units) can be continued, which increasesthe degree of freedom in design of the exposure apparatus such as theposition of the mark detection system. Note that by arranging thesubstrate measurement system for measuring position information onsubstrate P in the Z-axis direction near the mark detection system, thesubstrate measurement system can measure position information on Ycoarse movement stage 24 also on detection operation of the Z positionof the substrate. Alternately, the substrate measurement system may bearranged near projection optical system 16 so that the pair ofmeasurement tables 1782 may be used to measure the position informationon Y coarse movement stage 24 on detection operation of the Z positionof the substrate. Also, in the embodiment, when Y coarse movement stage24 is arranged at a substrate exchange position set apart fromprojection optical system 16, measurement beams of all heads of the pairof measurement tables 1782 move off from scales 1788 (or 684).Therefore, at least one head (which may either be a movable head or afixed head) may be provided facing at least one of the plurality ofscales 1788 (or 684) of Y coarse movement stage 24 arranged at thesubstrate exchange position, so that the substrate measurement systemcan measure the position information on Y coarse movement stage 24 alsoon the substrate exchange operation. Here, in the case the measurementbeams move off from scales 1788 (or 684) in all heads of the pair ofmeasurement tables 1782 before Y coarse movement stage 24 arrives at thesubstrate exchange position, or in other words, before the at least onehead arranged at the substrate exchange position faces scale 1788 (or684), at least one head is to be added arranged during the moving routeof Y coarse movement stage 24 so that the substrate measurement systemcan continue to measure the position information on substrate holder 32.Note that in the case of using the at least one head provided separatelyfrom the pair of measurement tables 1782, the linkage process describedearlier may be performed using the measurement information on the pairof measurement tables 1782.

Similarly, in the first to the twenty-second embodiments describedabove, the XZ head described earlier may be used instead of each X head74 x, along with using the YZ head described earlier instead of each Yhead 74 y. In such a case, with a pair of XZ heads and a pair of YZheads and an encoder system that these heads can face, positioninformation on at least one of rotation (θz) and tilt (at least one ofθx and θy) of a plurality of heads 74 x and 74 y may be measured.

Note that while a grating was formed (the surface is a grating surface)on the surface of scales 72, 78, 2072 and the like, for example, a covermember (such as glass or a thin film) that covers the grating may beprovided so that the grating surface is formed inside the scale.

Note that in the seventeenth embodiment described above, while the casehas been described in which one pair each of X head 80 x and Y head 80 yare provided at measurement table 1782, along with the heads formeasuring the position of Y coarse movement stage 24, one pair each of Xhead 80 x and Y head 80 y may be provided at the heads used formeasuring the position of Y coarse movement stage 24 without beingprovided at measurement table 1782.

Note that in the description so far, while the case has been describedin which the measurement directions within the XY plane of each headthat the substrate encoder system is equipped with is the X-axisdirection or the Y-axis direction, the embodiments are not limited tothis, and for example, instead of the two-dimensional grating, atwo-dimensional grating may be used that intersects in the X-axisdirection and the Y-axis direction and also has periodic directions intwo directions (called α direction and β direction for convenience)orthogonal to each other, and corresponding to this, as each headdescribed earlier, heads with measurement directions in the α direction(and the Z-axis direction) or the β direction (and the Z-axis direction)may be used. Also, in the first embodiment described earlier, instead ofeach X scale and Y scale, for example, a one-dimensional grating whoseperiodic direction is in the α direction or β direction maybe used, andcorresponding to this, as each head described earlier, heads withmeasurement directions in the α direction (and the Z-axis direction) orthe β direction (and the Z-axis direction) may be used.

Note that in the twentieth to the twenty-second embodiments describedabove, the first grating group may be structured by the row of X scalesdescribed earlier and the second grating group may be structured by therow of Y scales described earlier, and corresponding to this, aplurality of X heads (or XZ heads) that can face the X scales maybearranged at a predetermined spacing (spacing wider than the spacingbetween adjacent X scales) along with a plurality of Y heads (or YZheads) that can face the Y scales being arranged at a predeterminedspacing (spacing wider than the spacing between adjacent Y scales).

Note that in the twentieth to the twenty-second embodiments describedabove, as each scale arranged side by side in the X-axis direction orthe Y-axis direction, a plurality of scales of different lengths maynaturally be used. In this case, when two or more rows of scales havingthe same or orthogonal periodic directions are provided side by side,scales may be chosen with lengths that can be set so that the spacingbetween the scales do not overlap one another. That is, the arrangementspacing of the space between the scales structuring one row of scalesdoes not have to be an equal spacing. Also, for example, in the row ofscales on the coarse movement stage, the scales arranged in the centermay have a length in the X-axis direction physically longer than that ofthe scales (scales arranged at each edge in the row of scales) arrangedat both ends in the X-axis direction.

Note that in each of the sixth, the seventh, the sixteenth, and theseventeenth embodiments described above, while measurement tableencoders only have to measure position information on at least themeasurement table in the movement direction (the Y-axis direction in theembodiments described above), position information in at least onedirection (at least one of X, Z, θx, θy, and θz) different from themovement direction may also be measured. For example, positioninformation in the X-axis direction of a head (X head) whose measurementdirection is in the X-axis direction may also be measured, and positioninformation in the X-axis direction may be obtained with this Xinformation and measurement information on the X head. However, with thehead (Y head) whose measurement direction is in the Y-axis direction,position information in the X-axis direction orthogonal to themeasurement direction does not have to be used. Similarly, with the Xhead, position information in the Y-axis direction orthogonal to themeasurement direction does not have to be used. In short, positioninformation on substrate holder 622 and the like in the measurementdirection may be obtained, by measuring position information in at leastone direction different from the measurement direction of the heads, andusing this measurement information and measurement information on theheads. Also, for example, position information (rotation information) ofthe movable head in the θz direction may be measured using twomeasurement beams having different positions in the X-axis direction,and by using this rotation information with measurement information onthe X head and the Y head, position information on substrate holder 622in the X-axis and the Y-axis directions may be obtained. In this case,by arranging two of one of the X heads and Y heads and one of the otherof the X heads and Y heads so that the two heads having the samemeasurement direction are not arranged at the same position in thedirection orthogonal to the measurement direction, position informationin the X direction, the Y direction, and the θz direction can bemeasured. The other head preferably irradiates a position different fromthe two heads with the measurement beam. Moreover, if the heads ofencoders for movable heads is an XZ head or a YZ head, by arranging, forexample, two of one of the XZ heads and the YZ heads and one of theother so that the heads are not located on the same straight line, notonly Z information but also position information (tilt information) inthe ex direction and the θy direction can be measured. Positioninformation in the X-axis direction and the Y-axis direction may beobtained by at least one of the position information in the ex directionand the ey direction and the measurement information on the X heads andY heads. Similarly, position information on the movable heads in adirection different from the Z-axis direction may also be measured withXZ heads or YZ heads, and with this measurement information andmeasurement information on the movable heads, position information inthe Z-axis direction may be obtained. Note that if the scales of theencoders measuring the position information on the movable heads is asingle scale (grating area), then XYθz and Zθxθy can be measured bythree heads, however, in the case a plurality of scales (grating areas)are arranged separately, two each of X heads and Y heads, or two each ofXZ heads and YZ heads should be arranged, and the spacing in the X-axisdirection should be set so that the non-measurement period among thefour heads do not overlap one another. While this explanation was madeon the premise of the grating area being arranged parallel to the XYplane, this also can be applied similarly to a scale having a gratingarea parallel to the YZ plane.

Also, in each of the sixth, the seventh, the sixteenth, and theseventeenth embodiments described above, while the encoder was used asthe measurement device for measuring position information on themeasurement table, devices other than the encoder, such as, for example,an interferometer may also be used. In this case, for example, areflection surface may be provided at the movable head (or its holdingsection) and a measurement beam parallel to the Y-axis direction shouldbe irradiated on the reflection surface. Especially when the movablehead is moved only in the Y-axis direction, the reflection surface doesnot have to be large, which makes it easy to locally air-condition theoptical path of the interferometer beam to reduce air fluctuation.

Also, in the seventeenth embodiment described above, while the movableheads that irradiate the scales of Y coarse movement stage 24 withmeasurement beams are arranged one each in the Y-axis direction on bothsides of the projection system, the movable head may each be arranged ina plurality of numbers . For example, if adjacent movable heads(measurement beams) are arranged so that the measurement period of aplurality of movable heads partly overlaps in the Y-axis direction, theplurality of movable heads can continue to measure position informationeven if Y coarse movement stage 24 moves in the Y-axis direction. Inthis case, linkage process becomes necessary among the plurality ofmovable heads. Therefore, measurement information on a plurality ofheads arranged only on one side of the +Y side and the −Y side of theprojection system irradiating measurement beams on at least one scalemay be used to acquire correction information related to another headwhose measurement beam is within the scale, or measurement informationon not only the heads arranged on the +Y side but at least one headarranged on the other side may also be used. In short, of the pluralityof heads each arranged on the +Y side and the −Y side, measurementinformation on at least three heads irradiating measurement beams on thescale may preferably be used.

Also, with the substrate measurement system of the twentieth to thetwenty-second embodiments described above, while a plurality of scales(grating areas) is arranged separately in the scanning direction (theX-axis direction) in which substrate P is moved on scanning exposure,along with a plurality of heads being movable in the stepping direction(the Y-axis direction), conversely, the plurality of scales may bearranged in the step direction (the Y-axis direction) along with theplurality of heads being movable in the scanning direction (the X-axisdirection).

Also, in the first to the twenty-second embodiments described above, theheads of the encoder system do not necessarily have to have the entireoptical system that irradiates a scale with a beam from the lightsource, and may have only a part of the optical system, such as forexample, the light-emitting section.

Also, in the twentieth to the twenty-second embodiments described above,the heads of the pair of head bases 88 are not limited to thearrangement in FIG. 71 (X heads and Y heads are arranged on the +Y sideand the −Y side, and on the +Y side and the −Y side, the arrangement ofthe X head and Y head on one side is opposite to the other side in theX-axis direction), and for example, X heads and Y heads may be arrangedon the +Y side and the −Y side, and on the +Y side and the −Y side, thearrangement of the X head and Y head on one side may be the same as thatof the other side in the X-axis direction. However, in the case the Xposition of two Y heads is the same, when measurement of one of the twoX heads is cut off, then the θz information can no longer be measured,therefore, the X position of the two Y heads should preferably bedifferent.

Also, in the first to the twenty-second embodiments described above, inthe case the scales (scale members, grating section) irradiated with themeasurement beams from the heads of the encoder system are provided atthe projection optical system 16 side, the scales provided are notlimited to only a part of apparatus main section 18 (frame member)supporting projection optical system 16, and may be provided at thebarrel part of projection optical system 16.

Also, in the first to the twenty-second embodiments described above,while the case has been described in which the movement direction(scanning direction) of mask M and substrate P at the time of scanningexposure is in the X-axis direction, the scanning direction may be inthe Y-axis direction. In this case, long stroke direction of the maskstage has to be set in a direction rotated by 90 degrees around theZ-axis, along with having to rotate the direction of projection opticalsystem 16 by 90 degrees around the Z-axis.

Note that in the twentieth to the twenty-second embodiments describedabove, in the case a scale group (row of scales) in which a plurality ofscales is continuously arranged in the X-axis direction with gaps of apredetermined spacing in between is arranged on Y coarse movement stage24, in a plurality of rows at different positions separate in the Y-axisdirection (e.g. a position on one side (+Y side) and a position on theother side (−Y side) with respect to projection optical system 16), astructure may be employed so that the plurality of scale groups(plurality of rows of scales) can be used differently, depending on thearrangement of shots (shot map) on the substrate. For example, by makingthe whole length of the plurality of rows of scales different from oneanother between the rows of scales, the scales are applicable todifferent shot maps, and are also applicable to changes in the number ofshot areas formed on the substrate, as in the case of a four piecesetting and the case of a six piece setting. Also, along with thisarrangement, if position of gaps of each row of scales are made to be atdifferent positions in the X-axis direction, the heads corresponding toeach of the plurality of rows of scales do not move off away from themeasurement range simultaneously, which allows the number of sensorsconsidered as an undefined value in linkage process to be reduced andthe linkage process to be performed with high precision.

Also, in a scale group (row of scales) in which a plurality of scalesarranged in the X-axis direction is continuously arranged with gaps of apredetermined spacing in between on Y coarse movement stage 24, thelength in the X-axis direction of one scale (pattern for X-axismeasurement) may be a length that can be continuously measured only by alength of one shot area (the length in which a device pattern isirradiated and formed on a substrate when exposure is performed whilemoving the substrate on the substrate holder in the X-axis direction).This makes position measurement (position control) of substrate P(substrate holder) during scanning exposure easy, since relay control ofheads with respect to the plurality of scales does not have to beperformed during the scanning exposure of one shot area.

Also, in the first to the twenty-second embodiments described above, toacquire position information during the movement of the substrate stagedevice which moves to the substrate exchange position with the substrateloader, a scale for substrate exchange maybe provided at the substratestage device or at another stage device, and the substrate measurementsystem may use downward heads to acquire the position information on thesubstrate stage device. Or, a head for substrate exchange may beprovided at the substrate stage device or another stage device, andposition information on the substrate stage device may be acquired bymeasuring the scale or the scale for substrate exchange.

Also a position measurement system (e.g., a mark on a stage and anobservation system for observing the mark) separate from the encodersystem may be provided to perform exchange position control (management)of the stage.

Note that the substrate stage device only has to be able to at leastmove substrate P along the horizontal plane in long strokes, and in somecases does not have to be able to perform fine position setting indirections of six degrees of freedom. The substrate encoder systemaccording to the first to twenty-second embodiments described above canalso be suitably applied to such a two-dimensional stage device.

Also, the illumination light may be an ultraviolet light such as an ArFexcimer laser beam (wavelength 193 nm) or a KrF excimer laser beam(wavelength 248 nm), or a vacuum ultraviolet light such as an F₂ laserbeam (wavelength 157 nm). Also, as the illumination light, a harmonicwave may be used, which is a single-wavelength laser beam in theinfrared or visual region oscillated from a DFB semiconductor laser or afiber laser as vacuum ultraviolet light that is amplified by a fiberamplifier doped by, e.g. erbium (or both erbium and ytterbium), and thenis subject to wavelength conversion into ultraviolet light using anonlinear crystal. Also, a fixed laser (wavelength: 355 nm, 266 nm) mayalso be used.

Also, while the case has been described where projection optical system16 is a projection optical system of a multiple lens method equippedwith a plurality of optical systems, the number of projection opticalsystems is not limited to this, and one or more will be fine. Also, theprojection optical system is not limited to the projection opticalsystem of a multiple lens method, and may also be an Offner typeprojection optical system which uses a large mirror. Also, as projectionoptical system 16, a magnifying system or a reduction system may also beused.

Also, the exposure apparatus is not limited to the exposure apparatusfor liquid crystals which transfers the liquid crystal display devicepattern onto a square-shaped glass plate, and may also be widely appliedto an exposure apparatus for manufacturing organic EL(Electro-Luminescence) panels, an exposure apparatus for manufacturingsemiconductors, or to an exposure apparatus for manufacturing thin filmmagnetic heads, micro-machines, and DNA chips and the like. Also, theabove embodiments can be applied not only to an exposure apparatus formanufacturing micro-devices such as semiconductors, but also to anexposure apparatus that transfers a circuit pattern onto a glasssubstrate or a silicon wafer to manufacture a reticle or a mask used inan optical exposure apparatus, an EUV exposure apparatus, an X-rayexposure apparatus, and an electron-beam exposure apparatus.

Also, the object subject to exposure is not limited to a glass plate,and may also be other objects, such as, for example, a wafer, a ceramicsubstrate, a film member, or a mask blank. Also, in the case theexposure object is a substrate for a flat panel display, the thicknessof the substrate is not limited in particular, and includes a film-likesubstrate (a sheet-like member having flexibility). Note that theexposure apparatus of the embodiments is especially effective in thecase when the exposure object is a substrate whose length of a side ordiagonal length is 500 mm or more.

Electronic devices such as liquid crystal display devices (orsemiconductor devices) are manufactured through the steps such as; astep for performing function/performance design of a device, a step formaking a mask (or a reticle) on the basis of this design step, a stepfor making a glass substrate (or a wafer), a lithography step fortransferring a pattern of a mask (reticle) onto the glass substrate bythe exposure apparatus and the exposure method described in each of theabove embodiments, a development step for developing the glass substratewhich has been exposed, an etching step for removing by etching anexposed member of an area other than the area where the resist remains,a resist removing step for removing the resist that is no longernecessary since etching has been completed, a device assembly step, andan inspection step. In this case, in the lithography step, because thedevice pattern is formed on the glass substrate by carrying out theexposure method previously described using the exposure apparatus of theembodiments described above, a highly integrated device can bemanufactured with good productivity.

Note that the plurality of requirements in each of the embodimentdescribed above can be appropriately combined. Accordingly, a part ofthe plurality of requirements in each of the embodiments described abovedoes not have to be used.

Note that the disclosures of all publications, InternationalPublications, U.S. Patent Application Publications and U.S. Patentsrelated to the exposure apparatus and the like quoted in each of theembodiments above, in their entirety, are incorporated herein byreference as a part of the present specification.

INDUSTRIAL APPLICABILITY

As is described so far, the movable body apparatus and the moving methodof the present invention are suitable for moving an object. Also, theexposure apparatus of the present invention is suitable for performingexposure on an object. Also, the manufacturing method of a flat-paneldisplay of the present invention is suitable for manufacturing flatpanel displays. Also, the device manufacturing method of the presentinvention is suitable for manufacturing micro-devices.

REFERENCE SIGNS LIST

10 . . . liquid crystal exposure apparatus,

-   20 . . . substrate stage device,-   24 . . . Y coarse movement stage,-   32 . . . substrate holder,-   70 . . . substrate measurement system,-   72 . . . upward scale,-   74 x . . . downward X head-   74 y . . . downward Y head,-   78 . . . downward scale,-   80 x . . . upward X head,-   80 y . . . upward Y head,-   100 . . . main controller,-   P . . . substrate.

1. A movable body apparatus, comprising: a first movable body that holdsan object and can move in a first direction and a second directionintersecting with each other; a first measurement system in which one ofa first grating member having a plurality of grating areas arrangedmutually apart in the first direction and including measurementcomponents in the first direction and the second direction and aplurality of first heads each irradiating the first grating member witha measurement beam while moving in the first direction with respect tothe first grating member is provided at the first movable body, andwhich measures position information on the first movable body in thefirst direction by at least three first heads that irradiate at leastone of the plurality of grating areas with the measurement beams, of theplurality of first heads; a second movable body that is provided withthe other of the first grating member and the plurality of first heads,and can move in the second direction; a second measurement system inwhich one of a second grating member including measurement components inthe first direction and the second direction and a second headirradiating the second grating member with a measurement beam whilemoving in the second direction with respect to the second grating memberis provided at the second movable body, and the other of the secondgrating member and the second head is provided facing the second movablebody, and which measures position information on the second movable bodyin the second direction; and a control system that performs movementcontrol of the first movable body in directions of three degrees offreedom within a predetermined plane including the first direction andthe second direction, based on the position information measured by thefirst measurement system and the second measurement system, andcorrection information to compensate for measurement error of the firstmeasurement system occurring due to at least one of the first gratingmember, the plurality of first heads, and movement of the first movablebody.
 2. The movable body apparatus according to claim 1, wherein thecorrection information compensates for measurement error of the firstmeasurement system caused by at least one of deformation, displacement,flatness, and formation error in at least one of the plurality ofgrating areas.
 3. The movable body apparatus according to claim 1,wherein the correction information compensates for measurement error ofthe first measurement system caused by at least one of optical propertyand displacement in a direction different from the second direction ofat least one head of the plurality of first heads.
 4. The movable bodyapparatus according to claim 1, wherein the correction informationcompensates for measurement error of the first measurement system causedby a difference of position in a third direction orthogonal to thepredetermined plane between a reference surface and a grating surface ofthe first grating member, the reference surface being a referencesurface for position control of the first movable body or a referencesurface with which the object coincides on exposure operation of theobject.
 5. The movable body apparatus according to claim 4, wherein thefirst movable body is arranged below an optical system, and thereference surface includes an image plane of the optical system. 6-48.(canceled)
 49. The movable body apparatus according to claim 1, whereineach of the plurality of first heads has a measurement direction that isone of two directions intersecting each other within the predeterminedplane, and the at least three first heads used on measurement in thefirst measurement system include at least one first head whosemeasurement direction is in one of the two directions and at least twofirst heads whose measurement direction is in the other of the twodirections.
 50. The movable body apparatus according to claim 49,wherein the plurality of first heads includes at least two first headswhose measurement direction is in the first direction and at least twofirst heads whose measurement direction is in the second direction. 51.The movable body apparatus according to claim 1, wherein the pluralityof first heads can be moved relatively with the first movable body inthe second direction.
 52. The movable body apparatus according to claim1, wherein the plurality of first heads includes two first headsirradiating the measurement beams with a spacing in between that iswider than a spacing between a pair of adjacent grating areas of theplurality of grating areas in the first direction, and at least onefirst head whose measurement beam is different in position from themeasurement beam of at least one of the two first heads in the seconddirection.
 53. The movable body apparatus according to claim 1, whereineach of the plurality of grating areas has a reflective two-dimensionalgrating or two reflective one-dimensional gratings whose arrangementdirections are different from each other.
 54. The movable body apparatusaccording to claim 1, wherein the first grating member has a pluralityof scales on which each of the plurality of grating areas is formed. 55.The movable body apparatus according to claim 1, wherein the firstmeasurement system has a drive section that can move the plurality offirst heads in the second direction, and the control system controls thedrive section so that the measurement beam of each of the at least threefirst heads used for measurement in the first measurement system doesnot move off from the plurality of grating areas in the second directionwhile the first movable body is moving.
 56. The movable body apparatusaccording to claim 1, wherein each of the plurality of first heads has ameasurement direction in two directions that are one of two directionsintersecting each other within the predetermined plane and a thirddirection orthogonal to the predetermined plane, and the firstmeasurement system can measure position information on the first movablebody in directions of three degrees of freedom including the thirddirection, different from the directions of three degrees of freedomwithin the predetermined plane, using the at least three first heads.57. The movable body apparatus according to claim 1, wherein theplurality of first heads has at least four first heads, and while themeasurement beam of one first head of the at least four first headsmoves off from the plurality of grating areas, the measurement beams ofat least three remaining first heads are irradiated on at least one ofthe plurality of grating areas, and by the first movable body moving inthe first direction, the one first head having the measurement beam thatmoves off from the plurality of grating areas is switched, of the atleast four first heads.
 58. The movable body apparatus according toclaim 57, wherein the at least four first heads include two first headswhose measurement beams are different in position from each other in thefirst direction, and two first heads whose measurement beams aredifferent in position from the measurement beam of one of the two firstheads in the second direction and are different in position from eachother in the first direction, and the two first heads irradiate themeasurement beams with a spacing in between that is wider than a spacingbetween a pair of adjacent grating areas of the plurality of gratingareas in the first direction.
 59. The movable body apparatus accordingto claim 57, wherein the first grating member has at least two of theplurality of grating areas arranged mutually apart in the seconddirection, the at least four first heads irradiate each of the at leasttwo of the plurality of grating areas with the measurement beams via theat least two first heads whose measurement beams are different from eachother in position in the first direction, and the at least two firstheads irradiate the measurement beams with a spacing in between that iswider than a spacing between a pair of adjacent grating areas of theplurality of grating areas in the first direction.
 60. The movable bodyapparatus according to claim 59, wherein the grating member is providedat the first movable body, and the plurality of first heads is providedabove the first movable body, and the at least two of the plurality ofgrating areas include a pair of the plurality of grating areas arrangedon both sides of an object mounting area of the first movable body inthe second direction.
 61. The movable body apparatus according to claim57, wherein during movement of the first movable body in the firstdirection, a non-measurement section in which the measurement beams moveoff from the plurality of grating areas does not overlap in the at leastfour first heads.
 62. The movable body apparatus according to claim 61,wherein the plurality of first heads includes at least one first headwhose non-measurement section at least partly overlaps with thenon-measurement section of at least one of the at least four firstheads, and in measurement of position information on the first movablebody, of at least five first heads including the at least four firstheads and the at least one first head, at least three first headsirradiating the measurement beams on at least one of the plurality ofgrating areas are used.
 63. The movable body apparatus according toclaim 57, wherein the control system acquires correction information tocontrol movement of the first movable body using one first head whosemeasurement beam moves off from one grating area of the plurality ofgrating areas and which moves to irradiate another grating area adjacentto the one grating area, of the at least four first heads, based onmeasurement information on at least three remaining first heads, orposition information on the first movable body measured using the atleast three remaining first heads.
 64. The movable body apparatusaccording to claim 63, wherein the correction information is acquiredwhile each of the measurement beams of the at least four first heads isirradiated on at least one of the plurality of grating areas.
 65. Themovable body apparatus according to claim 63, wherein before themeasurement beam of one of the at least three remaining first headsmoves off from one of the plurality of grating areas, positioninformation on the first movable body is measured using at least threefirst heads including the one first head for which the correctioninformation has been acquired, instead of the one of the at least threeremaining first heads.
 66. The movable body apparatus according to claim63, wherein each of the plurality of first heads has a measurementdirection in two directions that are one of two directions intersectingeach other within the predetermined plane and a third directionorthogonal to the predetermined plane, the first measurement systemmeasures position information on the first movable body in directions ofthree degrees of freedom including the third direction, different fromthe directions of three degrees of freedom within the predeterminedplane, using the at least three first heads, and the control systemacquires correction information to control movement of the first movablebody in the directions of three degrees of freedom including the thirddirection using one first head whose measurement beam moves off from theone grating area and which moves to irradiate the another grating area,of the at least four first heads, based on measurement information inthe third direction of at least three remaining first heads, or positioninformation on the first movable body in the third direction measuredusing the at least three remaining first heads.
 67. An exposureapparatus, comprising: the movable body apparatus according to claim 1,and an optical system that irradiates a substrate, as the object, withan energy beam, and exposes the substrate.
 68. The exposure apparatusaccording to claim 67, further comprising: a frame member to support theoptical system, wherein the other of the first grating member and theplurality of first heads is provided at the frame member.
 69. Theexposure apparatus according to claim 67, wherein the substrate is heldin an opening of the first movable body, and the apparatus furthercomprising: a stage system that has a support section to support thefirst movable body and the substrate by levitation, and moves thesubstrate supported by levitation in at least the directions of threedegrees of freedom with the drive system.
 70. The exposure apparatusaccording to claim 67, further comprising: an illumination opticalsystem to illuminate a mask with illumination light, wherein the opticalsystem has a plurality of optical systems each projecting a partialimage of a pattern of the mask.
 71. The exposure apparatus according toclaim 70, wherein the substrate is scanned and exposed with theillumination light via the optical system, and the plurality of opticalsystems each project the partial image in a plurality of projectionareas whose positions are mutually different in a direction orthogonalto a scanning direction in which the substrate is moved in the scan andexposure.
 72. The exposure apparatus according to claim 67, wherein thesubstrate is scanned and exposed with the illumination light via theoptical system, and on the scan and exposure, the substrate is moved inthe first direction.
 73. The exposure apparatus according to claim 67,wherein the substrate is scanned and exposed with the illumination lightvia the optical system, and on the scan and exposure, the substrate ismoved in the second direction.
 74. The exposure apparatus according toclaim 67, wherein the substrate has at least one of a length of a sideand a diagonal length that is 500 mm or more, and is used in a flatpanel display.
 75. A flat-panel display manufacturing method,comprising: exposing a substrate using the exposure apparatus accordingto claim 67; and developing the substrate that has been exposed.
 76. Adevice manufacturing method, comprising: exposing a substrate using theexposure apparatus according to claim 67; and developing the substratethat has been exposed.
 77. A movable body apparatus, comprising: amovable body arranged below an optical system, that holds a substrate; adrive system that can move the movable body in a first direction and asecond direction orthogonal to each other within a predetermined planeorthogonal to an optical axis of the optical system; a measurementsystem in which one of a grating member with a plurality of gratingareas arranged mutually apart in the first direction and a plurality offirst heads each irradiating the grating member with a measurement beamand movable in the second direction is provided at the movable body, andthe other of the grating member and the plurality of first heads isprovided facing the movable body, the measurement system having ameasurement device in which one of a scale member and a second head isprovided at the plurality of first heads and the other of the scalemember and the second head is provided facing the plurality of firstheads, the measurement device measuring position information on theplurality of first heads in the second direction by irradiating thescale member with a measurement beam via the second head, and themeasurement system measuring position information on the movable body inat least directions of three degrees of freedom within the predeterminedplane, based on measurement information on at least three first headsthat irradiate at least one of the plurality of grating areas with themeasurement beam, of the plurality of first heads, and measurementinformation on the measurement device; and a control system thatcontrols the drive system based on correction information to compensatefor measurement error of the measurement device caused by at least oneof the scale member and the second head, and the position informationmeasured by the measurement system, wherein the measurement beam of eachof the plurality of first heads moves off from one grating area of theplurality of grating areas, and each of the plurality of first headsmoves to irradiate another grating area adjacent to the one gratingarea, while the movable body is moving in the first direction.
 78. Themovable body apparatus according to claim 77, further comprising: aframe member to support the optical system, wherein in the measurementdevice, one of the scale member and the second head is provided at theplurality of first heads, and the other of the scale member and thesecond head is provided at the optical system or the frame member. 79.The movable body apparatus according to claim 77, wherein the scalemember has a plurality of grating sections arranged mutually separate inthe second direction, the measurement device has a plurality of thesecond heads including at least two of the second heads whosemeasurement beams are different in position in the second direction, andthe at least two of the second heads are arranged at a spacing widerthan a spacing between a pair of adjacent grating sections of theplurality of grating sections in the second direction.
 80. The movablebody apparatus according to claim 79, wherein the plurality of secondheads include at least one second head whose measurement beam isdifferent in position from the measurement beam of at least one of theat least two of the second heads in one of the first direction and athird direction orthogonal to the predetermined plane.
 81. The movablebody apparatus according to claim 77, wherein the measurement devicemeasures position information on the plurality of first heads in adirection different from the second direction, by irradiating the scalemember at positions mutually different with a plurality of themeasurement beams.
 82. The movable body apparatus according to claim 77,wherein the measurement device measures position information on at leastone of rotation and tilt of the plurality of first heads.
 83. Themovable body apparatus according to claim 77, wherein the scale memberhas at least one of a reflective two-dimensional grating and tworeflective one-dimensional gratings whose arrangement directions aredifferent from each other.
 84. The movable body apparatus according toclaim 77, wherein the correction information compensates for measurementerror of the measurement device caused by at least one of deformation,displacement, flatness, and formation error in the scale member.
 85. Themovable body apparatus according to claim 77, wherein each of theplurality of first heads has a measurement direction in one of twodirections intersecting each other within the predetermined plane, andthe at least three first heads used on measurement in the measurementsystem include at least one first head whose measurement direction is inone of the two directions and at least two first heads whose measurementdirection is in the other of the two directions.
 86. The movable bodyapparatus according to claim 85, wherein the plurality of first headsincludes at least two first heads whose measurement direction is in thefirst direction and at least two first heads whose measurement directionis in the second direction.
 87. The movable body apparatus according toclaim 77, wherein the plurality of first heads include a first headhaving a measurement direction in a direction different from the firstdirection within the predetermined plane, and the measurement systemuses measurement information on the measurement device to measureposition information on the movable body using the first head having themeasurement direction different from the first direction.
 88. Themovable body apparatus according to claim 87, wherein the plurality offirst heads includes at least two first heads whose measurementdirection is in the first direction and at least two first heads whosemeasurement direction is in the second direction.
 89. The movable bodyapparatus according to claim 77, wherein the plurality of first headscan be moved relatively with the movable body in the second direction.90. The movable body apparatus according to claim 77, wherein theplurality of first heads includes two first heads irradiating themeasurement beams with a spacing in between that is wider than a spacingbetween a pair of adjacent grating areas of the plurality of gratingareas in the first direction, and at least one first head whosemeasurement beam is different in position from the measurement beam ofat least one of the two first heads in the second direction.
 91. Themovable body apparatus according to claim 77, wherein each of theplurality of grating areas has a reflective two-dimensional grating ortwo reflective one-dimensional gratings whose arrangement directions aredifferent from each other.
 92. The movable body apparatus according toclaim 77, wherein the grating member has a plurality of scales on whicheach of the plurality of grating areas is formed.
 93. The movable bodyapparatus according to claim 77, wherein the measurement system has adrive section that can move the plurality of first heads in the seconddirection, and the control system controls the drive section so that themeasurement beam of each of the at least three first heads used formeasurement in the measurement system does not move off from theplurality of grating areas in the second direction while the movablebody is moving.
 94. The movable body apparatus according to claim 77,wherein the measurement system has a plurality of movable sections thatcan move holding one first head or multiple first heads of the pluralityof first heads, and measures position information on the first head ateach of the plurality of movable sections by the measurement device. 95.The movable body apparatus according to claim 77, wherein each of theplurality of first heads has a measurement direction in two directionsthat are one of two directions intersecting each other within thepredetermined plane and a third direction orthogonal to thepredetermined plane, and the measurement system can measure positioninformation on the movable body in directions of three degrees offreedom including the third direction, different from the directions ofthree degrees of freedom within the predetermined plane, using the atleast three first heads.
 96. The movable body apparatus according toclaim 77, wherein the plurality of first heads has at least four firstheads, and while the measurement beam of one first head of the at leastfour first heads moves off from the plurality of grating areas, themeasurement beams of at least three remaining first heads are irradiatedon at least one of the plurality of grating areas, and by the movablebody moving in the first direction, the one first head having themeasurement beam that moves off from the plurality of grating areas isswitched, of the at least four first heads.
 97. The movable bodyapparatus according to claim 96, wherein the at least four first headsinclude two first heads whose measurement beams are different inposition from each other in the first direction, and two first headswhose measurement beams are different in position from the measurementbeam of one of the two first heads in the second direction and aredifferent in position from each other in the first direction, and thetwo first heads irradiate the measurement beams with a spacing inbetween that is wider than a spacing between a pair of adjacent gratingareas of the plurality of grating areas in the first direction.
 98. Themovable body apparatus according to claim 96, wherein the grating memberhas at least two of the plurality of grating areas arranged mutuallyapart in the second direction, the at least four first heads irradiateeach of the at least two of the plurality of grating areas with themeasurement beams via the at least two first heads whose measurementbeams are different in position from each other in the first direction,and the at least two first heads irradiate the measurement beams with aspacing in between that is wider than a spacing between a pair ofadjacent grating areas of the plurality of grating areas in the firstdirection.
 99. The movable body apparatus according to claim 98, whereinthe grating member is provided at the movable body, and the plurality offirst heads is provided above the movable body, and the at least two ofthe plurality of grating areas include a pair of the plurality ofgrating areas arranged on both sides of a substrate mounting area of themovable body in the second direction.
 100. The movable body apparatusaccording to claim 96, wherein during movement of the movable body inthe first direction, a non-measurement section in which the measurementbeams move off from the plurality of grating areas does not overlap inthe at least four first heads.
 101. The movable body apparatus accordingto claim 100, wherein the plurality of first heads includes at least onefirst head whose non-measurement section at least partly overlaps withthe non-measurement section of at least one of the at least four firstheads, and in measurement of position information on the movable body,of at least five first heads including the at least four first heads andthe at least one first head, at least three first heads irradiating themeasurement beams on at least one of the plurality of grating areas areused.
 102. The movable body apparatus according to claim 96, wherein thecontrol system acquires correction information to control movement ofthe movable body using one first head whose measurement beam moves offfrom the one grating area and which moves to irradiate the anothergrating area, of the at least four first heads, based on measurementinformation on at least three remaining first heads, or positioninformation on the movable body measured using the at least threeremaining first heads.
 103. The movable body apparatus according toclaim 102, wherein the correction information is acquired while each ofthe measurement beams of the at least four first heads is irradiated onat least one of the plurality of grating areas.
 104. The movable bodyapparatus according to claim 102, wherein before the measurement beam ofone of the at least three remaining first heads moves off from one ofthe plurality of grating areas, position information on the movable bodyis measured using at least three first heads including the one firsthead for which the correction information has been acquired, instead ofthe one of the at least three remaining first heads.
 105. The movablebody apparatus according to claim 102, wherein each of the plurality offirst heads has a measurement direction in two directions that are oneof two directions intersecting each other within the predetermined planeand a third direction orthogonal to the predetermined plane, themeasurement system measures position information on the movable body indirections of three degrees of freedom including the third direction,different from the directions of three degrees of freedom within thepredetermined plane, using the at least three first heads, and thecontrol system acquires correction information to control movement ofthe movable body in the directions of three degrees of freedom includingthe third direction using one first head whose measurement beam movesoff from the one grating area and which moves to irradiate the anothergrating area, of the at least four first heads, based on measurementinformation in the third direction of at least three remaining firstheads, or position information on the movable body in the thirddirection measured using the at least three remaining first heads. 106.An exposure apparatus, comprising: the movable body apparatus accordingto claim 77; and an optical system that irradiates the substrate with anenergy beam, and exposes the substrate.
 107. The exposure apparatusaccording to claim 106, further comprising: a frame member to supportthe optical system, wherein the other of the grating member and theplurality of first heads is provided at the frame member.
 108. Theexposure apparatus according to claim 107, wherein in the measurementsystem, the grating member is provided at the movable body, and theplurality of first heads is provided at the frame member, and in themeasurement device, the second head is provided at the plurality offirst heads, and the scale member is provided at the frame member. 109.The exposure apparatus according to claim 106, wherein the substrate isheld in an opening of the movable body, and the apparatus furthercomprising: a stage system that has a support section to support themovable body and the substrate by levitation, and moves the substratesupported by levitation in at least the directions of three degrees offreedom with the drive system.
 110. The exposure apparatus according toclaim 106, further comprising: an illumination optical system toilluminate a mask with illumination light, wherein the optical systemhas a plurality of optical systems each projecting a partial image of apattern of the mask.
 111. The exposure apparatus according to claim 110,wherein the substrate is scanned and exposed with the illumination lightvia the optical system, and the plurality of optical systems eachproject the partial image in a plurality of projection areas whosepositions are mutually different in a direction orthogonal to a scanningdirection in which the substrate is moved in the scan and exposure. 112.The exposure apparatus according to claim 106, wherein the substrate isscanned and exposed with the illumination light via the optical system,and on the scan and exposure, the substrate is moved in the firstdirection.
 113. The exposure apparatus according to claim 106, whereinthe substrate is scanned and exposed with the illumination light via theoptical system, and on the scan and exposure, the substrate is moved inthe second direction.
 114. The exposure apparatus according to claim106, wherein the substrate has at least one of a length of a side and adiagonal length that is 500 mm or more, and is used in a flat paneldisplay.
 115. A flat-panel display manufacturing method, comprising:exposing a substrate using the exposure apparatus according to claim106; and developing the substrate that has been exposed.
 116. A devicemanufacturing method, comprising: exposing a substrate using theexposure apparatus according to claim 106; and developing the substratethat has been exposed.
 117. A moving method, comprising: moving a firstmovable body holding an object in a first direction and a seconddirection intersecting each other; measuring position information on thefirst movable body in the first direction by a first measurement system,in the first measurement system one of a first grating member having aplurality of grating areas arranged mutually apart in the firstdirection and including measurement components in the first directionand the second direction and a plurality of first heads each irradiatingthe first grating member with a measurement beam while moving in thefirst direction being provided at the first movable body, and the firstmeasurement system measuring the position information on the firstmovable body in the first direction by at least three first headsirradiating at least one of the plurality of grating areas with themeasurement beams, of the plurality of first heads; moving the firstmovable body in the second direction by a second movable body providedwith the other of the first grating member and the plurality of firstheads; measuring position information on the second movable body in thesecond direction by a second measurement system, in the secondmeasurement system one of a second grating member including measurementcomponents in the first direction and the second direction and a secondhead irradiating the second grating member with a measurement beam whilemoving in the second direction being provided at the second movablebody, and the other of the second grating member and the second headbeing provided facing the second movable body; and performing movementcontrol of the first movable body in directions of three degrees offreedom within a predetermined plane including the first direction andthe second direction, based on the position information measured by thefirst measurement system and the second measurement system, andcorrection information to compensate for measurement error of the firstmeasurement system occurring due to at least one of the first gratingmember, the plurality of first heads, and movement of the first movablebody.
 118. An exposure method, comprising: moving the object in thefirst direction by the moving method according to claim 117; andirradiating the object moved in the first direction with an energy beam,and exposing the object.
 119. A flat-panel display manufacturing method,comprising: exposing a substrate, as the object, using the exposuremethod according to claim 118; and developing the substrate that hasbeen exposed.
 120. A device manufacturing method, comprising: exposing asubstrate, as the object, using the exposure method according to claim118; and developing the substrate that has been exposed.